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In this work, a detailed study of structural, electrical and magnetic characterization of (GaMn)Sb diluted magnetic semiconductors (DMS) is presented. (GaMn)Sb thin films were grown by DC magnetron co-sputtering method as an innovative procedure to fabricate III-V DMS. The presence of unusual Mn2Sb2 and Mn2Sb secondary phases, induced by substrate temperature and deposition time, were revealed through XRD measurements. Magnetization measurements allow determining crossover between a paramagnetic-like to a ferromagnetic-like behavior controlled by secondary phases. It was found that both, the magnetic remanence and magnetic coercivity, increases with substrate temperature. Interestingly, the magnetic response is paramagnetic at lower deposition times and substrate temperatures, and XRD measurements suggest the absence of Mn2Sb and Mn2Sb2 in secondary phases. For longer deposition times or higher substrate temperature, XRD shows the presence of Mn2Sb2 and Mn2Sb phases and ferromagnetic-like behavior. The DC resistivity of our samples was characterized and the carrier density was determined by Hall measurements and, in contrast with the reported in other studies, found them to be a p-type semiconductor with carrier densities as big as one order of magnitude larger than reported values. From the ferromagnetic-like samples, evidence of an anomalous Hall-effect in the sample was found, with higher magnetic saturation and a anomalous Hall conductivity of 2380 S/cm. All the results point to a contribution of the secondary phases to the overall magnetic response of the samples used, and suggest the importance of studying the formation of secondary phases in the growth of DMS, especially, for the case of (GaMn)Sb where Mn ion can have multiple oxidation states.

This work present structural, morphological, magnetic, and electrical properties of GaSb/Mn multilayer deposited via DC magnetron sputtering at room temperature and at 423 K. The samples are characterized by forming layers of 3, 6 and 12 periods of the GaSb/Mn structure. Through XRD patterns, it was possible to stablish the formation of GaSb, Mn 3 Ga, and Mn 2 Sb 2 phases. FTIR measurements present an optical interference associated with periodicity and the homogenous thickness of the layers. HR-SEM shows the multilayer architecture with columnar microstructure in the formation of layers with grain nucleation on the surface. A ferromagnetic-like behavior was observed in the multilayers at room temperature related to the domains and interlayers interaction. Additionally, the hysteresis curves present shifts attributed to the effect of exchange bias coupling. I-V curves show RESET-SET states of the multilayer system with bipolar resistive behavior, which can be modified by external magnetic fields. The resistive switching evidenced corresponds to the conductive mechanism based on the capacitive conductance and the formation of conductive filaments in multilayer structure.

A key issue in a cost–benefit assessment of an expansion of an airport is its impact on emissions of greenhouse gases. Both taxes and tradable permits can be used to put a price tag on emissions, but practitioners disagree on how to handle permits. Therefore, the paper offers a section clarifying how to handle permits in cost–benefit analysis, with a more formal treatment in the Appendix. The paper also discusses the impact on the outcome of the evaluation of alternative assumptions regarding how greenhouse gases are internalised. Both optimal Pigouvian taxes and tradable permits are considered.

Agave Tequilana Weber (ATW) is the base ingredient for preparing tequila liquor; tequila production yields tons of waste rich in cellulose representing environmental issues. Cellulose nanocrystals (CNC), the crystalline regions extracted from cellulose microcrystals, were obtained from the waste of ATW as an attractive alternative to reinforce polymeric materials. CNC were grafted with (poly (2-ethyl hexyl acrylate) to improve compatibility with hydrophobic polymers. The CNC pristine (CNCP) and grafted (CNCG) were dispersed in PLA (0.5, 1 and 2 wt.%), employing several melt processing stages. CNC distribution within PLA matrix was followed using SEM and TEM. Also, thermal properties were characterized through differential scanning calorimetry and thermogravimetric analysis. Thermal stability of nanocomposites increased with CNC, CNCG nanocomposites showed better results ( T d  ~ 370 °C) than CNCP nanocomposites ( T d  ~ 366 °C). The degree of crystallinity showed for CNCG (25.1%) was higher than for CNCP (21.1%) nanocomposites. The tensile properties were improved with CNCP (0.44 MPa) and CNCG (2.11 MPa) content. The CNC increased the shear properties of PLA melt and exhibited a strain-hardening behavior during elongational rheology test. The CNC and CNCG are an interesting alternative to modify the melt rheological behavior and the mechanical behavior in the solid-state of low melt strength polymers, which could be thermally degraded during processing. Composites could be used to produce films for the food industry through blow-extrusion processing. Graphical abstract

We present a virtual reality (VR) framework for controlling dual-arm robotic manipulators through immersive interfaces, integrating both simulated and real-world platforms. The system combines the Webots robotics simulator with Unreal Engine 5.6.1 to provide real-time visualization and interaction, enabling users to manipulate each arm’s tool point via VR controllers with natural depth perception and motion tracking. The same control interface is seamlessly extended to a physical dual-arm robot, enabling teleoperation within the same VR environment. Our architecture supports real-time bidirectional communication between the VR layer and both the simulator and hardware, enabling responsive control and feedback. We describe the system design and performance evaluation in both domains, demonstrating the viability of immersive VR as a unified interface for simulation and physical robot control.

The multilayer structure is a well-studied architecture for electronic and optoelectronic applications and more recently in spintronic devices. In this work, we present the structural, morphological, topographical, and magnetic properties of GaSb/Mn multilayers deposited via DC magnetron sputtering at room temperature and 423 K. Raman measurements evidence the formation of p-type GaSb layers with a contribution of electrons in the multilayer due to the neighboring Mn layer and the formation of effective interlayers. HR-SEM measurements show the multilayer architecture with columnar microstructure in the layer’s formation, while AFM micrographs allowed observing the changes in grain sizes (between 129 and 187 nm) and roughness (between 1.47 nm and 6.28 nm) with increasing number of layers. The formation of the interlayers between the GaSb and Mn layer was assayed in-depth spectroscopically via Rutherford backscattering studies. These interlayers were associated with diffusion processes during deposition and contributed to the magnetic behavior of multilayers. A ferromagnetic-like behavior was observed in the multilayers.

A key issue in a cost-benefit assessment of an expansion of an airport is its impact on emissions of greenhouse gases. Both taxes and tradable permits can be used to put a price tag on emissions, but practitioners disagree on how to handle permits. Therefore, the paper offers a section clarifying how to handle permits in cost-benefit analysis, with a more formal treatment in the Appendix. The paper also discusses the impact on the outcome of the evaluation of alternative assumptions regarding how greenhouse gases are internalised. Both optimal Pigouvian taxes and tradable permits are considered.

Magnesium (Mg) has been explored during the last few decades in the biomedical industry as a biodegradable implant. However, mechanical properties and corrosion resistance are still big concerns for clinical use. Therefore, this study proposes a suitable surface modification of the Mg by plasma electrolytic oxidation (PEO) to improve its corrosion resistance and biological performance. Mg samples were processed in a galvanostatic mode using an electrolytic solution of a phosphate compound supplemented with either potassium pyrophosphate or sodium-potassium tartrate. The obtained coatings were physiochemically characterized by SEM, XRD, EDS, and micro-Raman spectroscopy. The corrosion resistance of the coatings was studied using a hydrogen evolution setup and electrochemical tests. Finally, the biological performance of the material was evaluated by using an indirect test with osteoblasts. Obtained coatings showed a porous morphology with thicknesses ranging from 2 to 3 µm, which was closely dependent on the PEO solution. The corrosion resistance tests improved the degradation rate compared to the raw material. Additionally, an unreported active–passive corrosion behavior was evidence of a protective layer of corrosion products underneath the anodic coating. Indirect in vitro cytotoxicity assays indicated that the coatings improved the biocompatibility of the material. In conclusion, it was found that the produced coatings from this study not only lead to material protection but also improve the biological performance of the material and ensure cell survival, indicating that this could be a potential material used for bone implants.

Purpose In this work, praziquantel (PZQ) was incorporated into self-emulsifying drug delivery system (SEDDS) formulations to demonstrate that the increased apparent solubility and dissolution rate enhance intestinal permeation. Methods Solubility measurements of PZQ were performed in lipid excipients and hydrophilic substances; ternary phase diagrams were constructed with the excipients in which PZQ showed increased solubility. SEDDS formulations were characterized by globule size, the polydispersity index, zeta potential, the self-emulsification time, and morphology by scanning and transmission electron microscopy. The formulations were evaluated by performing in vitro dissolution profiles and permeation profiles in an ex vivo model. Results Four SEDDS formulations were identified that increased the apparent solubility of praziquantel by 60–150 times. The dispersion sizes obtained were < 350 nm, with polydispersity index values < 0.3, dispersion times < 60 s, and zeta potential values <  −25 mV. A notable increase in the PZQ dissolution rate was obtained compared with the reference drug product. The permeation profiles were adjusted to a first-order kinetic model, obtaining an apparent absorption rate constant (K ab ) up to 18 times higher for SEDDS formulations than for PZQ powder, while the apparent permeability (P app ) and the effective intestinal permeability (P eff ) values increased up to 18 times for SEDDS formulations compared with PZQ powder. Conclusion The incorporation of PZQ into a SEDDS increases its apparent solubility and dissolution rate, changes that significantly enhance the processes of intestinal permeability. This behavior can be applied to support formulations of drugs belonging to class IV of the biopharmaceutical classification system.

Polypyrrole (PPy) is considered a promising electrode material for supercapacitors (SCs) due to its high specific capacitance; however, it exhibits low long-term cycling stability. To address this issue, the introduction of nanostructured materials into the PPy matrix yields nanocomposites that exhibit enhanced capacitance and improved cycling stability. In this study, PPy/palygorskite (PPy/Pal) nanocomposites were synthesized via in situ chemical polymerization of pyrrole on Pal templates. To enhance the compatibility between PPy and the clay, the surface of Pal was modified with a silane coupling agent (Pal-S). In a half-cell configuration, the PPy/Pal-S electrodes exhibit better electrochemical performance in terms of specific capacitance, rate capability, and cycling stability than the PPy electrode. The PPy/Pal-S nanocomposites achieved a maximum specific capacitance of 218 F g −1 and retained 91% of their initial capacitance after 500 CV cycles. Moreover, the fabricated symmetric supercapacitor device elaborated with the PPy/Pal-S electrodes delivered a specific capacitance of 15 F g −1 at 3 mA cm −2 , an energy density of 0.9 Wh kg −1 , a power density of 55 W kg −1 with a cycling stability of 72% after 2000 GCD cycles, in a voltage range of 0.7 V. This study presents a novel strategy for constructing a 1D core/sheath PPy/Pal-S structure, which combines the advantageous properties of PPy (pseudocapacitance and electrical conductivity) and Pal-S clay (mechanical and chemical stability, 1D morphology, mesoporosity, and nanoscale size). Understanding the synergistic effects provides valuable insights for designing electrode materials with superior performance.