(Elsevier, 2025-07-30) Amghar, Nabil; Ivorra-Martinez, Juan; Perejón Pazo, Antonio; Hanaor, Dorian; Gurlo, Aleksander; Ramírez Rico, Joaquín; Pérez Maqueda, Luis Allan; Sánchez Jiménez, Pedro Enrique; Química Inorgánica; Física de la Materia Condensada; Ministerio de Ciencia e Innovación (MICIN). España
This study investigates the development of porous calcium-based monoliths via freeze-casting (FC) as a novel approach for thermochemical energy storage, particularly within the Calcium Looping (CaL) process. The freeze-casting technique enabled the fabrication of scaffolds with controlled porosity using polyvinyl alcohol (PVA) as a binder. Experimental results demonstrated that freeze-cast monoliths exhibited superior multicycle performance under various carbonation and calcination conditions. The FC-CaCO3 monolith achieved the highest residual conversion of 68.1 % under mild vacuum calcination conditions (780 °C, 0.1 bar CO2), significantly surpassing other configurations. Tests conducted in an inert atmosphere also yielded favorable results, with a conversion of 56.1 %, outperforming equivalent raw powder samples. The enhanced performance is attributed to improved CO2 interaction with the porous structure, mitigating sintering effects and preserving active surface area. Morphological observations by X-ray tomography and SEM confirmed limited particle sintering after multiple cycles, maintaining a reactive surface that supported consistent conversion rates. The pore size distribution of the material evolves upon cycling resulting in an increased microporosity, while the pore network maintains a low tortuosity (τ ~ 1.5–2.0). The addition of dopants such as ZrO2 and SiO2 did not enhance performance, as the monoliths' inherent structure provided sufficient stability. These findings highlight freeze-casting as a promising method for creating advanced porous materials suitable for energy storage applications.
(Institute of Physics Publishing Ltd., 2025-04-22) Moreira, Pedro; Carvalho, Davide; Abreu, Rodrigo; Alba Carranza, María Dolores; Ramírez Rico, Joaquín; Fortunato, Elvira; Martins, Raúl A.; Pinto, Joana V.; Carlos, Emanuel; Coelho, João; Física de la Materia Condensada; Fundaçao para a Ciencia e a Tecnologia (FCT); Junta de Andalucía; European Union
Graphene and its composites have attracted much attention for applications in energy storage systems. However, the toxic solvents required for the exfoliation process have hampered the exploitation of its properties. In this work, graphene dispersions are obtained via liquid phase exfoliation (LPE) of graphite in cyrene, an environmentally friendly solvent with solubility parameters like those of N-methyl-2-pirrolidone. The obtained dispersions with a concentration of 0.2 mg ml−1 comprised multilayered graphene sheets with lateral sizes in the hundreds of nanometers, as confirmed by scanning electron microscopy, transmission electron microscopy, and Raman spectroscopy. Mixing the obtained dispersions with ethanol made it possible to collect the graphene, which was redispersed in 2-Propanol. This active material was used to fabricate supercapacitor electrodes using a scalable spray deposition method on carbon nanotube (CNT) current collectors with the aid of vinyl masks. The device, tested with a PVA/LiCl gel electrolyte, achieved a specific capacitance of 3.4 mF cm−2 (0.015 mA cm−2). In addition, the devices show excellent cycling stability (>10 000 cycles at 0.5 mA cm−2) and good mechanical properties, losing less than 10% of initial capacitance after 1000 bending cycles. This work demonstrates the adaptability of liquid-phase exfoliation to produce graphene sustainably, providing the proof-of-concept for further 2D materials processing and green microsupercapacitor (MSC) fabrication.
(Elsevier, 2024-11) Casas Rodríguez, Antonio; Šentjurc, Tjaša; Díez-Quijada Jiménez, Leticia; Pichardo Sánchez, Silvia; Žegura, Bojana; Jos Gallego, Ángeles Mencía; Cameán Fernández, Ana María; Nutrición y Bromatología, Toxicología y Medicina Legal; Ministerio de Ciencia, Innovación y Universidades (MICIU). España; Slovenian Research Agency
Cylindrospermopsin (CYN), a cyanotoxin with worldwide distribution, is gaining increased attention due to its bioaccumulation potential and toxicological effects. Previous research suggests that CYN may interact with other environmental contaminants, potentially amplifying its toxicity. To address this concern, the present study investigated the combined effects of CYN with arsenic (As) and cadmium (Cd) on human immune cell lines, Jurkat and THP-1. Cytotoxicity tests showed that As and Cd significantly decreased the viability of both cell lines after 24 and 48 h of exposure. The EC50 (24 h) values for Jurkat cells were 13.15 ± 1.97 (As) and 36.92 ± 3.77 μM (Cd), respectively, while for THP-1, the EC50 (24 h) values were 46.48 ± 0.17 for As and 55.09 ± 4.98 μM for Cd. Furthermore, individual contaminants and their mixtures with CYN impaired monocyte differentiation into macrophages. The effect on mRNA expression of some cytokines (TNF-α, INF-γ, IL-2, IL-6 and IL-8) was also assessed. In the Jurkat cell line, As upregulated IL-8 expression while Cd increased the expression of all interleukins. Exposure to binary combinations (CYN + As, and CYN + Cd) increased IL-2 and INF-γ expression. In THP-1 cells, As elevated IL-8 and INF-γ expression, whereas Cd caused an increase in TNF-α and INF-γ expression. Exposure to CYN + As up-regulated IL-8 and INF-γ expression, while the CYN + Cd combination down-regulated TNF-α expression. These findings highlight the complex interactions between contaminants, emphasizing the need for evaluating combined effects in risk assessments.
(Elsevier, 2024-12) Cascajosa Lira, Antonio; Pichardo Sánchez, Silvia; Baños, Alberto; Torre, José Manuel de la; Ayala-Soldado, Nahum; González-Pérez, José A.; Jiménez-Morillo, Nicasio T.; Jos Gallego, Ángeles Mencía; Cameán Fernández, Ana María; Nutrición y Bromatología, Toxicología y Medicina Legal; Junta de Andalucía; Ministerio de Ciencia, Innovación y Universidades (MICIU). España
Propyl-propane thiosulfonate (PTSO) is an organosulfur compound found in Allium spp., commonly used in animal nutrition and various agri-food applications. Extensive studies have demonstrated the safety of PTSO for feed use, including investigations into genotoxicity, mutagenicity, and subchronic toxicity in rats. However no kinetic or metabolic study has been previously performed. This study aimed to conduct an in vivo toxicokinetic assessment of PTSO in rats. For this purpose, eighteen Sprague Dawley rats received an oral dose of 175 mg/kg via gastric gavage. Plasma and tissue samples (brain, stomach, liver, lung, kidney, spleen, and testicle) were collected at specific intervals (10 min, 20 min, 30 min, 1h, 2h, 4h, 6h, 8h, and 24h) and analyzed using Gas Chromatography-High-Resolution Mass Spectrometry, Pyrolysis Gas Chromatography -High-Resolution Mass Spectrometry, and Ultra-High Performance Liquid Chromatography-Tandem Mass Spectrometry to detect PTSO and its metabolites. PTSO was not detected in plasma or solid tissues throughout the sampling period; however, phase I and phase II metabolites were identified in both matrices. The toxicokinetic profile of s-propyl mercaptocysteine (CSSP), a significant metabolite, exhibited a well-correlated model. In the stomach, CSSP reached peak concentrations of 495.63 ± 6.53 ng/mL, while lower concentrations of 123.59 ± 8.35 ng/mL were observed in plasma. Furthermore, CSSP demonstrated high water solubility and rapid excretion, with a plasma half-life of 0.66 ± 0.05 h. Overall, these findings substantiate the safety profile of PTSO for specific agri-food applications under the conditions investigated.