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Insights into the kinetics of furfural production from different monomers and polymers derived from biomass in a subcritial water reaction medium intensified by CO2 as pressurization agent
No full textA systematic kinetic study was conducted on the production of furfural from different sugar monomers, including xylose, arabinose and glucose, and xylan, a biopolymer rich in pentoses, in a subcritical water reaction medium intensified by the presence of CO2 as pressurization agent. The temperature range was from 150 to 200 °C, and different catalysts were employed, with CrCl3 as a Lewis acid catalyst. Glucose yielded very low amounts of furfural. Regarding pentoses, different reaction pathways were analyzed. The proposed mechanism involved the presence of the corresponding ketoses, xylulose and ribulose, from xylose and arabinose, respectively, as intermediates in furfural production. Formic acid was identified as the main degradation product in this reaction medium. It was concluded that formi acid was released into the medium from both pentoses and furfural. Pentose aldoses isomerization to ketoses, followed by furfural formation was the primary reaction pathway in this system. When using an acidic resin such as Nafion NR50 as catalyst, the isomerization of xylose was the rate-controlling step. When starting from xylan, similar furfural yields were obtained, but producitivity values evaluated over time were higher for xylose due to the two-step process involved in furfural production from xylan. The molecular weight distribution in the xylan system showed an initial increase for fractions in the range of 282–150 Da, while fractions of molecular weights higher than 1074 Da appeared only at the end of the treatment, likely due to the formation of different polymeric products.This work was supported by the Agencia Estatal de Investigación [grant numbers PID2022-136385OB-I00, TED2021-129311B-I00, PDC2022-133443-I00] and the Junta de Castilla y León (JCyL) and the European Regional Development Fund (ERDF) [grant number BU027P23]. A. E. Illera postdoctoral contract was funded by BU027P23. H Candela-Gil pre-doctoral contract was funded by JCyL and the European Social Fund [ORDEN EDU/1009/2024]
Microwave technology as a green and fast alternative for furfural production and biomass pre-treatment using corn stover: energetic and economic evaluation
No full textPressurized microwave treatments were used for the production of furfural using three different pentose-containing materials with different structural complexity levels; pure xylose, xylan from corn core and corn stover. Only water was used as the one-pot reaction medium, as an alternative to the frequently used organic solvents. The presence of CrCl3 as a Lewis acid catalyst was essential for furfural production. In general, higher temperature and longer treatments led to higher furfural yield, although treatment times over 40 minutes did not show any improvement. Using the severity factor (logR0) and the power consumption it was possible to determine that for equal furfural production treatments, it was more energy requiring to maintain a lower temperature during more time, than to perform shorten treatments at higher temperature. Best MW treatment conditions for xylose were 200 °C for 25 minutes, with a furfural yield of 43 %, which corresponded to a logR0 of 2.56. When treating xylan and corn stover, lower furfural yields were achieved under these conditions due to higher energy requirements to break the structural components, being 39 and 23 %, respectively. When treating corn stover under these conditions, best energy consumption values per amount of generated furfural were found, being 0.8 kWh/ g furfural, what is equivalent to the emission of 195 g CO2/ g furfural, a much lower value than other MW tested conditions. MW treatments were proposed as a pre-treatment to enrich biomass in cellulose while producing furfural with an environmentally friendly technology.This work was supported by the Agencia Estatal de Investigación (AEI), Ministerio de Ciencia e Innovación (MICINN) and Next Generation UE (Plan de Recuperaciónn, Transformación y Resiliencia) [grant numbers TED2021–129311B-I00 and PDC2022–133443-I00] and the Junta de Castilla y León (JCyL) and the European Regional Development Fund (ERDF) [grant number BU050P20]. P. Barea predoctoral contract was funded by JCyL and the European Social Fund (ESF) by ORDEN EDU/1868/2022, de 19 de diciembre
Learn Chinese with mnemonics (beginner level)
No full textLearn Chinese with mnemonics (beginner level) es un libro diseñado para acompañarte en tus primeros pasos hacia el aprendizaje del chino mandarín, una lengua fascinante y llena de matices. Escrito en inglés y pensado para principiantes, este manual combina claridad, creatividad y eficacia mediante el uso de mnemotecnia, una técnica pedagógica que te ayuda a recordar vocabulario, gramática y pronunciación de forma divertida y duradera.
El libro se estructura en cinco capítulos que abordan aspectos esenciales del idioma: desde la pronunciación y el sistema tonal, hasta los radicales, caracteres y estructuras gramaticales básicas. Cada elemento se presenta con ejemplos contextualizados y trucos de memoria que facilitan enormemente el proceso de aprendizaje
Dataset on the effectiveness of a music programme for pre-school pupils in a community of Castilla y León
No full textThe data set is made up of the four data collection instruments that were used for the evaluation
of the music programme designed for Early Childhood Education students. These are: the CER
questionnaire for the evaluation of musical expression, attentional processes and social skills together with
an Inventory of Signs, and for the evaluation of the programme, the CEP and CEF questionnaires
Mi escuela en el mundo
No full text"Mi escuela en el mundo" es el resultado de un trabajo colaborativo en el que participa alumnado de todos los niveles educativos, investigadores de diferentes países y especialistas de diversos campos profesionales.
Esta obra incluye 39 fotografías vinculadas a la educación. Las imágenes están presentadas por las alumnas y los alumnos del Grado de Pedagogía que las buscaron. Después esta propuesta del alumnado sirve de inspiración a especialistas de distintos campos (educación, periodismo, fotografía...).
También contiene 39 dibujos realizados por niñas y niños de centros educativos de Burgos (España) y de una escuela de Uganda. Los dibujos se han llevado a cabo partiendo de frases relativas a la educación.
Todas las fotografías y los dibujos cuentan con una descripción escrita. La lectura oral de los textos (descripciones y opiniones de los especialistas) ha sido realizada y grabada por estudiantes de distintos niveles (desde educación infantil hasta doctorado), incluyendo centros de educación especial, personas adultas y población inmigrante.
En su conjunto, el libro responde a las directrices del Diseño Universal para el Aprendizaje (DUA).
"Mi escuela en el mundo" promueve una reflexión sobre la educación y su importancia en un mundo tan diverso como el nuestro. No busca la comparación entre escuelas o países con más o menos recursos, sino que quien lo lea valore y aprecie a la educación como una potente herramienta para el desarrollo en cualquier contexto.
Finalmente, se propone a las lectoras y lectores su participación activa en el proyecto.Financiada por la Fundación Caja Círculo y presentada en la Sala de Exposiciones de Caja Círculo (actual Sala de Exposiciones Pedro Torrecilla
Deepening the effect of selectively crushed wind-turbine blade on the dimensional stability and high-temperature resistance of concrete
No full textSelectively Crushed Wind-Turbine Blade (SCWTB) is obtained through knife crushing of panels from wind-turbine blades. Two thirds of SCWTB weight consist of GFRP-composite fibers, which may improve both dimensional stability and high-temperature resistance of concrete. In this investigation, the evaluation of such aspects in concrete containing 1.5 %, 3.0 %, 4.5 % and 6.0 % SCWTB by volume is addressed. For this purpose, plastic shrinkage, drying shrinkage, total shrinkage, and thermal expansion were evaluated regarding dimensional stability, while resistance to high temperatures was assessed through accelerated-aging and thermal-shock tests. The results revealed that 6.0 % SCWTB reduced by half concrete plastic shrinkage, and total shrinkage by 40–50 % at 7 days and by 10–20 % at 91 days. Furthermore, the initial thermal strain was decreased from SCWTB contents of 3.0 %, which in turn reduced the linear thermal expansion coefficient, which had a value of 1.49·10−5 °C−1 in concrete with 6.0 % SCWTB. Finally, concrete with SCWTB maintained adequate compressive strength after accelerated aging and air-heating thermal shock, reaching values above 40 MPa, and halved the loss of flexural strength when added in a content of 6.0 %. Scanning electron microscopy revealed that high temperatures caused micro-cracks that started in weak zones and propagated along the glass fibers of GFRP, but the bond between the cementitious matrix and the GFRP-composite fibers was ideal, so the matrix fractured instead of the fibers slipping when loading. The improvements induced by SCWTB were statistically significant, so this waste can be considered a value-added material in terms of the concrete behavior analyzed.This research work was supported by the Spanish Ministry of Science, Innovation and Universities MICIU, AEI, EU, ERDF and NextGenerationEU/PRTR [grant numbers PID2023-146642OB-I00; 10.13039/501100011033; TED2021-129715B-I00; FPU21/04364]; the Junta de Castilla y León (Regional Government) and ERDF [grant number UIC-231; BU033P23; BU066-22]; and, finally, the University of Burgos [grant number SUCONS, Y135.GI]
Fuentes alternativas de conocimiento para el desarrollo de las competencias para la cultura democrática: una propuesta práctica utilizando metodologías activas
Full text linkEn línea con la preocupación del Consejo de Europa de formar ciudadanos
comprometidos con los valores democráticos y capaces de afrontar los retos del siglo
XXI, la investigación tiene como objetivo explorar cómo desarrollar la educación
democrática en el aula de 1º de Bachillerato de Historia del Mundo Contemporáneo a
través de las fuentes alternativas de conocimiento.
La investigación se basa en una propuesta didáctica innovadora titulada “La música
en la Primera Guerra Mundial, de Granados…a Iron Maiden”. Esta propuesta,
diseñada para desarrollar diez competencias para la cultura democrática
seleccionadas de entre las que fija el Consejo de Europa, busca conectar los
contenidos curriculares de la materia con el desarrollo de las competencias
democráticas a través de fuentes alternativas y la metodología de Aprendizaje Basado
en Problemas (APB).
A partir de su aplicación en un grupo-clase de 1º de Bachillerato del IES Diego de Silóe
de Burgos, que involucró a 32 estudiantes, se realizó una investigación en la que se
empleó metodología cualitativa. Se utilizaron como instrumentos la observación
directa, debates grupales, entrevistas escritas, análisis de cuadernos de trabajo y la
creación de un vídeo final.
Los resultados, codificados y categorizados para evaluar el impacto de la propuesta
en el desarrollo de las competencias agrupadas en las cuatro categorías del Modelo
de Competencias para la cultura democrática del Consejo de Europa (Valores,
Actitudes, Habilidades y Conocimiento crítico del mundo), apuntan a que la
experiencia:
fomenta la participación de los estudiantes,
enriquece su comprensión de conceptos clave como democracia, justicia,
equidad, igualdad y Estado de derecho,
resulta efectiva en el desarrollo de la capacidad para conectar y establecer
relaciones entre pasado y presente y por lo tanto al desarrollo de la conciencia
histórica
contribuye al desarrollo del pensamiento crítico y análisis de fuentes.
Finalmente, la metodología APB y la plataforma Genially mostraron ser herramientas
valiosas para el aprendizaje cooperativo y las habilidades de investigación, lo que abre
la posibilidad al desarrollo de este tipo de experiencias en el aula.In line with the Council of Europe's concern to train citizens committed to democratic
values and capable of facing the challenges of the 21st century, the research aims to
explore how to develop democratic education in the 1st year of the Baccalaureate (Alevels)
in the Contemporary World History subject through alternative sources of
knowledge.
The research is based on an innovative teaching proposal entitled ‘Music in the First
World War, from Granados... to Iron Maiden’. This proposal, designed to develop ten
competences for democratic culture selected from among those set by the Council of
Europe, seeks to connect the curricular contents of the subject with the development
of democratic competences through alternative sources of knowledge and the Problem-
Based Learning (PBL) methodology.
Based on its application in a group-class of 1st year Baccalaureate students at IES
(high school) Diego de Siloé in Burgos, Spain, which involved 32 students, a research
was carried out using qualitative methodology. The instruments used were direct
observation, group discussions, written interviews, analysis of workbooks and the
creation of a final video.
The results, coded and categorised to assess the impact of the proposal on the
development of the competences grouped in the four categories of the Council of
Europe's Model of Competences for a democratic culture (Values, Attitudes, Skills and
Critical knowledge of the world), indicate that the experience:
encourages students' participation,
enriches their understanding of key concepts such as democracy, justice,
equity, equality and the rule of law,
is effective in developing the ability to connect and make connections between
past and present and thus in developing historical awareness and
contributes to the development of critical thinking and analysis of sources.
Finally, the APB methodology and the Genially platform proved to be valuable tools for
cooperative learning and research skills, which opens the possibility for the
development of such experiences in the classroom
La integración sensorial como herramienta para el manejo de conductas asociadas al TDAH en el alumnado de educación infantil
No full textEn el presente trabajo se muestra una revisión documental teórica sobre la integración
sensorial en niños y niñas que presentan manifestaciones asociadas al Trastorno por
déficit de atención e hiperactividad en la etapa de Educación Infantil. Surgiendo tras la
necesidad por parte de los maestros/as de conocer recursos que les ayude a entender y
manejar determinadas conductas que se encuentran en el día a día del aula. Para ello, se
realiza una investigación exhaustiva sobre la integración sensorial y el trastorno por
déficit de atención e hiperactividad en la infancia, conociendo las manifestaciones de este
trastorno en la etapa de Educación infantil. También, se plantearon relaciones entre el
TDAH y la disfunción del procesamiento sensorial, con el propósito de proporcionar y
aplicar estrategias de integración sensorial en el aula como propuesta efectiva para
prevenir y beneficiar al alumnado que presenta síntomas relacionados con este trastorno
en esta etapa, y así, poder intervenir para mejorar su proceso de enseñanza-aprendizaje
desde edades tempranas.This paper presents a theoretical literature review on sensory integration in young
children who exhibit behaviors associated with Attention Deficit Hyperactivity Disorder
(ADHD) during the early childhood education stage. It arises from the need expressed by
teachers to access resources that help them understand and manage certain behaviors
encountered in the daily classroom environment. To this end, an in-depth investigation is
carried out on sensory integration and ADHD in childhood, focusing on how this disorder
manifests during early education. Additionally, connections between ADHD and sensory
processing dysfunction are explored, with the aim of providing and applying sensory
integration strategies in the classroom as an effective proposal to prevent and support
students showing symptoms related to this disorder at this stage. This would allow for
early interventions to improve their teaching and learning processes from a young age
