Effect of the porous structure in carbon materials for CO2 capture at atmospheric and high-pressure

Activated carbons prepared from petroleum pitch and using KOH as activating agent exhibit an excellent behavior in CO2 capture both at atmospheric (∼168 mg CO2/g at 298 K) and high pressure (∼1500 mg CO2/g at 298 K and 4.5 MPa). However, an exhaustive evaluation of the adsorption process shows that the optimum carbon structure, in terms of adsorption capacity, depends on the final application. Whereas narrow micropores (pores below 0.6 nm) govern the sorption behavior at 0.1 MPa, large micropores/small mesopores (pores below 2.0–3.0 nm) govern the sorption behavior at high pressure (4.5 MPa). Consequently, an optimum sorbent exhibiting a high working capacity for high pressure applications, e.g., pressure-swing adsorption units, will require a poorly-developed narrow microporous structure together with a highly-developed wide microporous and small mesoporous network. The appropriate design of the preparation conditions gives rise to carbon materials with an extremely high delivery capacity ∼1388 mg CO2/g between 4.5 MPa and 0.1 MPa. Consequently, this study provides guidelines for the design of carbon materials with an improved ability to remove carbon dioxide from the environment at atmospheric and high pressure.

Validación de la versión española del cuestionario Physician Readiness To Manage Intimate Partner Violence Survey (PREMIS)

Fundamentos: El Physician Readiness to Manage Intimate Partner Violence Survey (PREMIS) es uno de los cuestionarios más completos en el contexto internacional para la valoración de la capacidad de respuesta frente a la violencia del compañero íntimo por los profesionales de Atención Primaria de Salud. El objetivo de este estudio fue determinar la fiabilidad, consistencia interna y validez de constructo de la versión española de este cuestionario. Métodos: Tras la traducción, retrotraducción y valoración de la validez de contenido del cuestionario, se distribuyeron en una muestra de 200 profesionales de medicina y enfermería de 15 centros de atención primaria de 4 Comunidades Autónomas en 2013 (Comunidad Valenciana, Castilla León, Murcia y Cantabria). Se calcularon los coeficientes alfa de Cronbach, los de correlación intraclase y rho de Spearman (test-retest). Resultados: la versión española del PREMIS incluyó 64 ítems. El coeficiente α de Cronbach fue superior a 0,7 o muy cercano a ese valor en la mayoría de los índices. Se obtuvo un coeficiente de correlación intraclase de 0,87 y un coeficiente de Spearman de 0,67 que muestran una fiabilidad alta. Todas las correlaciones observadas para la escala de opiniones, la única tratada como estructura factorial en el cuestionario PREMIS, fueron superiores a 0,30. Conclusiones: el PREMIS en español obtuvo una buena validez interna, alta fiabilidad y capacidad predictiva de las prácticas auto-referidas por médicos(as) y enfermeros(as) frente a casos de violencia del compañero íntimo en centros de atención primaria.

Evolution of extracellular polymeric substances produced in two submerged membrane bioreactors working at high sludge age

This research paper deals with the evolution of the extracellular polymeric substances (EPS) produced in the mixed liquor of two 25 L bench-scale membrane bioreactors (MBRs), with micro (MF-MBR) and ultrafiltration (UF-MBR) submerged membranes. The conclusion focuses on the relationship between the operation and how EPS respond, demonstrating that significant changes in EPS concentration were commonly observed when abrupt changes in the operational conditions took place. Bound EPS (EPSb) showed moderate positive statistical correlations with sludge age and MLSS for the two MBRs. Soluble EPS (EPSs), on the other hand, showed a moderate negative statistical correlation between EPSs with the two parameters analyzed for MF-MBR and no correlation with the UF-MBR was found. With respect to the composition of EPS, EPSb were mostly made up of proteins (44–46%) whereas in EPSs, the three components (proteins, carbohydrates, and humic substances) appeared in approximately the same proportion. The statistical analysis exhibited strong positive correlations between EPSb and their constituents, however for EPSs, the correlation was strong only with carbohydrates and moderate with humic substances.

Intra-population variation and geographic correlation in Canthon humectus hidalgoensis using FTIR-ATR spectroscopy

In some cases external morphology is not sufficient to discern between populations of a species, as occurs in the dung beetle Canthon humectus hidalgoensis Bates; and much less to determine phenotypic distances between them. FTIR-ATR spectroscopy show several advantages over other identification techniques (e.g. morphological, genetic, and cuticular hydrocarbons analysis) due to the non-invasive manner of the sample preparation, the relative speed of sample analysis and the low-cost of this technology. The infrared spectrum obtained is recognized to give a unique ‘fingerprint’ because vibrational spectra are specific and unique to the molecular nature of the sample. In our study, results showed that proteins, amino acids and aromatic ethers of insect exocuticle have promising discriminative power to discern between different populations of C. h. hidalgoensis. Furthermore, the correlation between geographic distances between populations and the chemical distances obtained by proteins + amino acids + aromatic ethers was statistically significant, showing that the spectral and spatial information available of the taxa together with appropriated chemometric methods may help to a better understanding of the identity, structure, dynamics and diversity of insect populations.