Interplay of Interfacial and Rheological Properties on Drainage Reduction in CO2 Foam Stabilised by Surfactant/Nanoparticle Mixtures in Brine

Although nanoparticles (NPs) are known to increase foam stability, foam stabilisation is not observed in all surfactant/NP combinations. The present study evaluates the stability of CO2 foams containing surfactant/NP mixtures with attractive or repulsive electrostatic interactions at the low pH imposed by CO2 in the presence of a high-salinity brine. Three ionic surfactants and two oxide NPs (SiO2 and Al2O3) were used in combinations of similar or opposite charges. Surface tension, viscosity, ζ-potential and hydrodynamic size experiments allowed the analysis of CO2 foam stability based on the impact of surfactant–NP interactions on bulk and interfacial properties. All oppositely charged systems improved the foam half-life; however, a higher NP concentration was required to observe a significant effect when more efficient surfactants were present. Both bulk viscosity and rigidity of the interfacial films drastically increased in these systems, reducing foam drainage. The mixture of SiO2 with a zwitterionic surfactant showed the greatest increase in CO2 foam stability owing to the synergy of these effects, mediated by attractive interactions. This study showed that the use of NPs should be tailored to the surfactant of choice to achieve an interplay of interfacial and rheological properties able to reduce foam drainage in applications involving CO2 foam in brine

Identificación de riesgos ambientales en el laboratorio de radioquímica de la facultad de ciencias y tecnologías nucleares

Organizations of all kinds are more and more interested in reaching and demonstrating a sustainable environmental performance by means of the control of the risks of their activities, products and services on the environment. The main purpose of the present investigation is to identify the environmental risks in the Radiochemistry Laboratory of the Faculty of Science and Nuclear Technologies (FCTN), allowing the organization to evaluate, to control, to minimize and/or to eliminate the environmental associated risks at the laboratory. In order to achieve such purpose, it was carried out an environmental diagnosis of the current situation of the laboratory and afterwards, it was made the evaluation of the environmental risks detected by means of the Managerial Procedure of Integrated Risks. There were also set out measures to diminish significant environmental risksOrganizaciones de todo tipo están cada vez más interesadas en alcanzar y demostrar un sostenido desempeño ambiental mediante el control de los riesgos de sus actividades, productos y servicios sobre el ambiente. La presente investigación tiene como objetivo identificar los riesgos ambientales en el Laboratorio de Radioquímica de la Facultad de Ciencias y Tecnologías Nucleares (FCTN), permitiéndole a la organización evaluar, controlar, minimizar y/o eliminar dichos riesgos asociados al ambiente en el laboratorio. Para ello se realizó un diagnóstico ambiental de la situación actual del laboratorio y seguidamente se realizó la evaluación de los riesgos ambientales detectados mediante el Procedimiento de Gestión de Riesgos Integrados. Finalmente se proponen medidas para minimizar los riesgos ambientales significativos

Dataset for "Core-shell spheroidal hydrogels produced via charge-driven interfacial complexation"

The dataset for "Core-Shell spheroidal Hydrogels produced via charge-driven interfacial complexation" contains data, in the form of excel and txt files, for the figures shown in the main manuscript and the electronic supplementary information (ESI). The study focuses on the structure of the spheroidal hydrogels (SH) and their resilience in aqueous media. Furthermore, SH are used as microreactors for biocatalysis, providing a proof-of-concept for this material. The dataset contains data regarding the structural information of the spheroidal hydrogels (SH) (e.g. shell thickness, small angle X-rays scattering, Z-potential and oscillatory rheology) their stability in solvents with different osmotic pressure and ionic strength (e.g. swelling kinetic, swelling ratio) and the enzymatic activity to support a proof-of-concept of the SH. Specification of the materials and methods employed throughout the data collection are available in the main manuscript. Each excel sheet is specific for a set of data acquired utilising the same protocol.Methodology, experimental conditions and data treatment is described in the main manuscript.In the Excel file named "Data_Core_Shell_Hydrogels“, the data are presented in separate sheets, each of which is labelled as for the figure presented in the manuscript. The spreadsheet named: Fig. 2b shows the data regarding the thickness of the spheroidal hydrogel (SH) shell. Fig. 2c contains data regarding the Leakage and retention of surface active molecules Fig. 3 contains the data of the swelling dynamic of the SH in different conditions (Di_water, 1000 mM NaCl and 0.1 wt% PAA) Fig. 4a contains data for the Swelling Ratio (SR) as function of the osmotic pressure. Fig. 4b-Top contains data for the Z-potential measurements of a CCNF dispersion as function of the NaCl concentration. Fig. 4b-Bottom contains data for the oscillatory rheology measurements of a 2 wt% CCNF dispersion as function of the NaCl concentration. Fig. 6 contains the data of the enzymatic activity measurements. The txt files contains small angle X-rays scattering (SAXS) data presented in Fig. 5a. Each txt file is named as for sample name used in Fig. 5a

Identification of organic compounds in Cajío Peloid (Cuba)

"Thennal muds ("peloids") are a typical example of natural sediments used in the treatment of different pathologies. Nowadays, because of their use in therapeutics, relax and cosmetic issues, a proper management of peloids is of increasing importance. Peloid characterization and monitoring for quality control purposes are therefore the main aspects of peloid management. Organic chemical quality is directly related with the biological active compounds and the therapeutic properties of peloidsto he used in human health and with the determination suitable contamination. This study was performed to characterize the organic fraction of Cajio peloid (Cuba) in order to identify the organic components with possible biological effects and establish its natural or anthropogenic origin. For this purpose, a procedure with chromatographic analysis and mass spectrometry detection has been performed. More than 40 compounds were identified, in Cajio peloid, mainly of natural origin. Among them were found alkanes, steroids, fatty acids, alcohols and other heteroatoms compounds, some of them with reported biological activity in their isolated form as antioxidant, analgesic, anti-inflammatory, and others. The results provide evidence for medical interpretation of the therapeutic action of Cajio peloid in the treatment of inflammatory and dermatological diseases and contribute to the understanding of pelotherapy, giving some scientific basis for its future development.

Physicochemical characterization, elemental speciation and hydrogeochemical modeling of Santa Lucía peloid used for therapeutic uses

"Santa Lucia peloid is a sediment, extracted from salt mines, used in pelotherapy in Cuban primary health care services. Therefore, in addition to classical quality control analyses of total metal concentrations in sediments, speciation and complementary analyses are required to understand potential geochemical element availability for their use in human health. The present study was conducted to characterize the Santa Lucia peloid, based on the total metal content and geochemical speciation of major elements and transition metals (Cr, Cu, Fe, Ni, Mn, Pb and Zn), using a sequential extraction procedure and inductively couple plasma emission techniques. In order to predict the distribution of majoritarian and trace elements in different geochemical fractions, the physicochemical parameters, the particle size (electronic microscopy), mineralogy (X-ray diffraction), and the hydrogeochemical models (Pourbaix phase diagrams) were used. The results showed that the predominant cation was Na with high mobility and exchange capacity; meanwhile most of the trace elements studied (Cr, Pb, Ni) in this investigation appeared in the less mobile fractions, which suggested low availability in the sediment, under the studied conditions. The findings were useful to predict the behavior of the metals regarding solubility, potential motility and availability in the sediment, and it was concluded that most of the metals are strongly retained in the peloid and that sediment was considered as non-polluted, according to USEPA normative.

Physicochemical characterization, elemental speciation and hydrogeochemical modeling of Santa Lucía peloid used for therapeutic uses

"Santa Lucia peloid is a sediment, extracted from salt mines, used in pelotherapy in Cuban primary health care services. Therefore, in addition to classical quality control analyses of total metal concentrations in sediments, speciation and complementary analyses are required to understand potential geochemical element availability for their use in human health. The present study was conducted to characterize the Santa Lucia peloid, based on the total metal content and geochemical speciation of major elements and transition metals (Cr, Cu, Fe, Ni, Mn, Pb and Zn), using a sequential extraction procedure and inductively couple plasma emission techniques. In order to predict the distribution of majoritarian and trace elements in different geochemical fractions, the physicochemical parameters, the particle size (electronic microscopy), mineralogy (X-ray diffraction), and the hydrogeochemical models (Pourbaix phase diagrams) were used. The results showed that the predominant cation was Na with high mobility and exchange capacity; meanwhile most of the trace elements studied (Cr, Pb, Ni) in this investigation appeared in the less mobile fractions, which suggested low availability in the sediment, under the studied conditions. The findings were useful to predict the behavior of the metals regarding solubility, potential motility and availability in the sediment, and it was concluded that most of the metals are strongly retained in the peloid and that sediment was considered as non-polluted, according to USEPA normative.

Dataset for "Core-shell spheroidal hydrogels produced via charge-driven interfacial complexation"

The dataset for "Core-Shell spheroidal Hydrogels produced via charge-driven interfacial complexation" contains data, in the form of excel and txt files, for the figures shown in the main manuscript and the electronic supplementary information (ESI). The study focuses on the structure of the spheroidal hydrogels (SH) and their resilience in aqueous media. Furthermore, SH are used as microreactors for biocatalysis, providing a proof-of-concept for this material. The dataset contains data regarding the structural information of the spheroidal hydrogels (SH) (e.g. shell thickness, small angle X-rays scattering, Z-potential and oscillatory rheology) their stability in solvents with different osmotic pressure and ionic strength (e.g. swelling kinetic, swelling ratio) and the enzymatic activity to support a proof-of-concept of the SH. Specification of the materials and methods employed throughout the data collection are available in the main manuscript. Each excel sheet is specific for a set of data acquired utilising the same protocol

Dataset for "Core-shell spheroidal hydrogels produced via charge-driven interfacial complexation"

The dataset for "Core-Shell spheroidal Hydrogels produced via charge-driven interfacial complexation" contains data, in the form of excel and txt files, for the figures shown in the main manuscript and the electronic supplementary information (ESI). The study focuses on the structure of the spheroidal hydrogels (SH) and their resilience in aqueous media. Furthermore, SH are used as microreactors for biocatalysis, providing a proof-of-concept for this material. The dataset contains data regarding the structural information of the spheroidal hydrogels (SH) (e.g. shell thickness, small angle X-rays scattering, Z-potential and oscillatory rheology) their stability in solvents with different osmotic pressure and ionic strength (e.g. swelling kinetic, swelling ratio) and the enzymatic activity to support a proof-of-concept of the SH. Specification of the materials and methods employed throughout the data collection are available in the main manuscript. Each excel sheet is specific for a set of data acquired utilising the same protocol