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1.
ACS Appl Mater Interfaces ; 14(27): 30772-30785, 2022 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-35793095

RESUMEN

Separation of volatile organic compounds is one of the most studied processes in industry. TAMOF-1 is a homochiral metal-organic framework with a crystalline network of interconnected ≈1 nm channels and has high thermal and chemical stability. Thanks to these features, it can resolve racemic mixtures of chiral drugs as a chiral stationary phase in chromatography. Interestingly, the particular shape and size of its channels, along with the presence of metallic centers and functional groups, allow establishing weak but significant interactions with guest molecules. This opens interesting possibilities not only to resolve racemates but also to separate other organic mixtures, such as saturated/unsaturated and/or linear/branched molecules. In search of these applications, we have studied the separation of volatile organic compounds in TAMOF-1. Monte Carlo simulations in the grand-canonical ensemble have been carried out to evaluate the separation of the selected molecules. Our results predict that TAMOF-1 is able to separate xylene isomers, hexane isomers, and benzene-cyclohexane mixtures. Experimental breakthrough analysis in the gas phase and also in the liquid phase confirms these predictions. Beds of TAMOF-1 are able to recognize the substitution in xylenes and the branching in hexanes, yielding excellent separation and reproducibility, thanks to the chemical and mechanical features of this material.

2.
Dalton Trans ; 50(5): 1808-1815, 2021 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-33464245

RESUMEN

The stability of metal-organic frameworks is a key factor in many applications in some fields that require working under harsh conditions. It is known that a large number of MOFs are vulnerable to humid air. It means that when they are exposed to water, a structural collapse of the crystal happens. In this work, Molecular Dynamics simulations using a reactive force field have been performed to study the stability of MOF-74 against the adsorption of catechol, resorcinol and hydroquinone in the presence of water. We reproduced the water instability of Zn-MOF-74 and we studied the resistance of the structure. Our simulations showed that the three isomers generate a volume change in the framework but the structural collapse does not happen. In contrast, for water-isomer mixtures, there is structural collapse. Not only do catechol, resorcinol and hydroquinone not behave as stabilizing agents but they do enhance the hydration effect on the structure.

3.
Rev Lat Am Enfermagem ; 22(3): 504-10, 2014.
Artículo en Inglés, Portugués, Español | MEDLINE | ID: mdl-25029064

RESUMEN

OBJECTIVE: understand the everyday and the imaginary of Nursing students in their knowledge socialization process through the Problem-Based Learning (PBL) strategy. METHOD: Action Research, involving 86 students from the second year of an undergraduate Nursing program in Spain. A Critical Incident Questionnaire and Group interview were used. Thematic/categorical analysis, triangulation of researchers, subjects and techniques. RESULTS: the students signal the need to have a view from within, reinforcing the criticism against the schematic dualism; PBL allows one to learn how to be with the other, with his mechanical and organic solidarity; the feeling together, with its emphasis on learning to work in group and wanting to be close to the person taking care. CONCLUSIONS: The great contradictions the protagonists of the process, that is, the students experience seem to express that group learning is not a form of gaining knowledge, as it makes them lose time to study. The daily, the execution time and the imaginary of how learning should be do not seem to have an intersection point in the use of Problem-Based Learning. The importance of focusing on the daily and the imaginary should be reinforced when we consider nursing education.


Asunto(s)
Educación en Enfermería/métodos , Teoría de Enfermería , Aprendizaje Basado en Problemas , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
4.
Rev. latinoam. enferm. (Online) ; 22(3): 504-510, May-Jun/2014.
Artículo en Inglés | LILACS, BDENF | ID: lil-714852

RESUMEN

OBJECTIVE: understand the everyday and the imaginary of Nursing students in their knowledge socialization process through the Problem-Based Learning (PBL) strategy. METHOD: Action Research, involving 86 students from the second year of an undergraduate Nursing program in Spain. A Critical Incident Questionnaire and Group interview were used. Thematic/categorical analysis, triangulation of researchers, subjects and techniques. RESULTS: the students signal the need to have a view from within, reinforcing the criticism against the schematic dualism; PBL allows one to learn how to be with the other, with his mechanical and organic solidarity; the feeling together, with its emphasis on learning to work in group and wanting to be close to the person taking care. CONCLUSIONS: The great contradictions the protagonists of the process, that is, the students experience seem to express that group learning is not a form of gaining knowledge, as it makes them lose time to study. The daily, the execution time and the imaginary of how learning should be do not seem to have an intersection point in the use of Problem-Based Learning. The importance of focusing on the daily and the imaginary should be reinforced when we consider nursing education. .


OBJETIVO: compreender o cotidiano e o imaginário dos alunos de Enfermagem em seu processo socializador do conhecimento, através da estratégia de Aprendizagem Baseada em Problemas. MÉTODO: Pesquisa-Ação, desenvolvida com 86 alunos da segunda turma de um curso de graduação em Enfermagem, na Espanha. Utilizou-se um Questionário de Incidências Críticas e Entrevista Grupal, análise temática/categorial, triangulação de investigadores, sujeitos e técnicas. RESULTADOS: os estudantes indicaram a necessidade de se ter uma visão de dentro, reforçando a crítica contra o dualismo esquemático; a Aprendizagem Baseada em Problemas possibilita: aprender a estar com o outro, com sua solidariedade mecânica e orgânica; o sentir juntos, com ênfase no aprender a trabalhar em grupo e querer estar próximo daquele que cuida. CONCLUSÕES: as grandes contradições vividas pelos protagonistas do processo, os estudantes, parecem expressar que a aprendizagem grupal não é uma forma de ganhar conhecimentos, ao tirar seu tempo para estudar. O cotidiano, o tempo de execução e o imaginário de como precisa ser a aprendizagem parece não possuir um ponto de encontro na utilização da Aprendizagem Baseada em Problemas. Reforça-se a importância de enfocar o cotidiano e o imaginário quando se pensa na educação em enfermagem. .


OBJETIVO: comprender lo cotidiano y lo imaginario de los alumnos de Enfermería en su proceso socializador del conocimiento a través de la estrategia del Aprendizaje Basado en Problemas (ABP). MÉTODO: Investigación Acción, desarrollada con 86 alumnos de 2º curso de Grado en Enfermería en España. Se utilizó Cuestionario de Incidencias Críticas y Entrevista grupal. Análisis temático/categorial, triangulación de investigadores, sujetos y técnicas. RESULTADOS: los estudiantes señalan la necesidad de tener una visión desde dentro, reforzando la crítica al dualismo esquemático; el ABP posibilita aprender a estar con otro, con su solidaridad mecánica y orgánica; el sentir juntos, con su énfasis en aprender a trabajar en grupo y querer estar próximo de aquel que cuida. CONCLUSIONES: Las grandes contradicciones que viven los protagonistas del proceso, los estudiantes, parecen expresar que el aprendizaje grupal no sea una forma de adquirir conocimientos, al incidir en que les quita tiempo para estudiar. Lo cotidiano, el tiempo de ejecución, y lo imaginario de cómo precisa ser el aprendizaje, parecen no tener un punto de encuentro en la utilización del Aprendizaje Basado en Problemas. Reforzar la importancia de enfocar lo cotidiano y lo imaginario, cuando pensamos en la educación en enfermería. .


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Adulto Joven , Teoría de Enfermería , Aprendizaje Basado en Problemas , Educación en Enfermería/métodos
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