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Obtención de nanocelulosa a partir de residuos lignocelulósicos de la industria agroalimentaria
No full textEn el presente Trabajo Fin de Máster (TFM), se ha llevado a cabo una revisión
bibliográfica a cerca de la nanocelulosa, con el objetivo de comprender sus propiedades,
aplicaciones y métodos de obtención. En particular, se ha enfocado en el uso de
biomasa lignocelulósica (generada como subproducto de la industria agroalimentaria)
como materia prima para su transformación en materiales nanocelulósicos. Se subraya
la importancia de gestionar adecuadamente los residuos de esta industria, la cual
produce 140 Gt/año de desechos, para mitigar impactos ambientales como la
contaminación y el cambio climático. Esta biomasa no solo contiene celulosa, sino
también otros componentes estructurales como la hemicelulosa y la lignina, que deben
ser eliminados antes de transformar la celulosa en nanocelulosa. El presente trabajo
aborda las estrategias para lograr este objetivo.
Con todo, este TFM explora la transición hacia una economía circular mediante la
valorización de estos subproductos de la industria agroalimentaria para obtener
materiales nanocelulósicos de alto valor añadido, materiales que presentan un gran
interés en sectores como el farmacéutico, tecnológico y alimentario, debido a sus
múltiples aplicaciones industriales, gracias a sus propiedades de biodegradabilidad,
biocompatibilidad y alta resistencia mecánica.In this Master Thesis (TFM), a literature review on nanocellulose has been conducted
with the aim of understanding its properties, applications, and methods of production.
Specifically, the focus has been on the use of lignocellulosic biomass, generated as a
by-product of the agro-food industry, as a raw material for its transformation into
nanocellulosic materials. The importance of properly managing the waste from this
industry, which produces 140 Gt/year of waste, is highlighted to mitigate environmental
impacts such as pollution and climate change. This biomass not only contains cellulose
but also other structural components such as hemicellulose and lignin, which must be
removed before transforming the cellulose into nanocellulose. This work addresses
strategies to achieve this goal.
This TFM explores the transition towards a circular economy by valorising these byproducts from the agro-food industry to obtain high value-added nanocellulosic
materials. These materials are of great interest in sectors such as pharmaceuticals,
technology, and food due to their multiple industrial applications, thanks to their
biodegradability, biocompatibility, and high mechanical strength
Estudios de adsorción y desorción de furfural empleando carbón activo y Amberlite XAD-4
No full textThe valorisation of solid agricultural waste remains a current challenge. The concept of a biorefinery arises from increasing concerns about environmental issues, as it is an efficient and sustainable way to produce valuable organic compounds from lignocellulosic byproducts, thereby maximizing their value. Corn is the most widely produced cereal globally, and Spain contributes approximately four million tons. Additionally, it is estimated that by 2030, global production of this cereal will increase by 160 million tons, reaching 1.3 billion tonnes. Corn stover has a high content of hemicellulose, cellulose, and lignin, making it a good raw material for the production of furfural. Furfural is a heterocyclic organic compound identified as a platform chemical with various subsequent applications: as an extractant, fungicide, raw material in the synthesis of various chemicals, and as a flavour and fragrance enhancer in the food industry. It is also a precursor to many other compounds of interest, such as succinic acid and furfuryl alcohol. Furfural is produced from the hydrolysis of hemicellulose, generally through acid hydrolysis and dehydration of xylose. This study analysed the selective recovery of furfural from corn stover subcritical water hydrolysates using an adsorption/desorption process, which are more environmentally and economically sustainable hydrolysis and purification methods. Specifically, this work evaluated the effect of the type of adsorbent, the mass/volume ratio, and the presence of impurities (mainly xylose and carboxylic acids) on the furfural adsorption yield, as well as compared batch and fixed bed treatments. After the study, under optimal working conditions (5 g of XAD-4, 75 ml of furfural hydrolysate, adsorption process at 25°C for 60 min, desorption process at 50°C for 30 min, and in a fixed bed), the results showed that the most selective adsorbent for furfural recovery was the Amberlite XAD-4 polymeric resin, with a furfural recovery from the corn waste subcritical water hydrolysate of 66.2% and a purity close to 91.3%.The valorisation of solid agricultural waste remains a current challenge. The concept of a biorefinery arises from increasing concerns about environmental issues, as it is an efficient and sustainable way to produce valuable organic compounds from lignocellulosic byproducts, thereby maximizing their value. Corn is the most widely produced cereal globally, and Spain contributes approximately four million tons. Additionally, it is estimated that by 2030, global production of this cereal will increase by 160 million tons, reaching 1.3 billion tons. Corn agricultural waste, such as stalks and leaves, have a high content of hemicellulose, cellulose, and lignin, making them a good raw material as biomass for the production of furfural. Furfural is a heterocyclic organic compound identified as a platform chemical with various subsequent applications: as an extractant, fungicide, raw material in the synthesis of various chemicals, and as a flavor and fragrance enhancer in the food industry. It is also a precursor to many other compounds of interest, such as succinic acid and furfuryl alcohol. Furfural is produced from the hydrolysis of hemicellulose, generally through acid hydrolysis and dehydration of xylose.This study analyzed the selective recovery of furfural from corn waste subcritical water hydrolysates using an adsorption/desorption process, which are more environmentally and economically sustainable hydrolysis and purification methods. Specifically, this work evaluated the effect of the type of adsorbent, the mass/volume ratio, and the presence of impurities (mainly xylose and carboxylic acids) on the furfural adsorption yield, as well as compared batch and fixed bed treatments. After the study, under optimal working conditions (5 g of XAD-4, 75 ml of furfural hydrolysate, adsorption process at 25°C for 60 min, desorption process at 50°C for 30 min, and in a fixed bed), the results showed that the most selective adsorbent for furfural recovery was the Amberlite XAD-4 polymeric resin, with a furfural recovery from the corn waste subcritical water hydrolysate of 66.2% and a purity close to 91.3%
Estudio e implementación de mantenimiento basado en condición de máquina de coextrusión en taller de preparación
No full textEn los talleres de mantenimiento en Michelin Aranda de Duero, la filosofía de trabajo lleva siendo la misma mucho tiempo y se encuentra desactualizada respecto a la optimización de este tipo de labor en la industria. Debido a esto, en este trabajo se va a desarrollar la evolución que se está haciendo en el taller de mantenimiento de OPF en una máquina piloto, gracias al mantenimiento basado en condición (CBM).
Dicho tipo de mantenimiento permite dedicar menos tiempo a la intervención inmediata (que conlleva paradas en producción), reducir la degradación en las diferentes piezas analizadas, prevenir roturas de algún elemento y por tanto un ahorro económico muy importante para la empresa.
Este mantenimiento se logra debido a la programación de unos análisis que son los que se van a explicar en este trabajo, además de su posterior notificación automática y su visualización de alertas en unas pantallas.In the maintenance workshops at Michelin Aranda de Duero, the work philosophy has remained the same for a long time and is outdated regarding the optimization of this type of work in the industry. Due to this, this project will develop the evolution being carried out in the OPF maintenance workshop on a pilot machine, thanks to condition-based maintenance (CBM).
This type of maintenance allows for less time spent on immediate intervention (which involves production stops), reduces the degradation of the various analyzed parts, prevents the breakage of any component, and thus leads to significant cost savings for the company.
This maintenance is achieved through the scheduling of analyses that will be explained in this project, as well as their subsequent automatic notification and alert visualization on screens
Personalising the Training Process with Adaptive Virtual Reality: A Proposed Framework, Challenges, and Opportunities
No full textComunicación presentada en: International Conference on Extended Reality, XR Salento 2024, held in Lecce, Italy during September 4–7, 2024This work presents a conceptual framework that integrates Artificial Intelligence (AI) into immersive Virtual Reality (iVR) training systems, aiming to enhance adaptive learning environments that dynamically respond to individual users’ physiological states. The framework uses real-time data acquisition from multiple sources, including physiological sensors, eye-tracking and user interactions, processed through AI algorithms to personalise the training experience. By adjusting the complexity and nature of training tasks in real time, the framework seeks to maintain an optimal balance between challenge and skill, fostering an immersive learning environment. This work details some methodologies for data acquisition, the preprocessing required to synchronise and standardise diverse data streams, and the AI training techniques essential for effective real-time adaptation. It also discusses logistical considerations of computational load management in adaptive systems. Future work could explore the scalability of these systems and their potential for self-adaptation, where models are continuously refined and updated in real-time based on incoming data during user interactions.This work was supported by the Ministry of Science and Innovation of Spain under project PID2020-119894GB-I00, co-financed through European Union FEDER funds and the project Humanaid (TED2021-129485B-C43) cofunded by “NextGenerationEU”/PRTR funds. It was also supported through REMAR Project (CPP2022-009724) funded by the Ministry of Science and Innovation of Spain (MCIN/AEI/ 10.13039/501100011033) and by the European Union NextGenerationEU/PRTR. And, finally, it was supported through the Consejería de Educación of the Junta de Castilla y León and the European Social Fund through a pre-doctoral grant (EDU/875/2021)
Nutrition education in the midwife consultation room. A cross sectional survey in Spain
No full textBackground: Diet during pregnancy is a key factor in the success of pregnancy. However, several studies have found pregnant women have low adherence to dietary recommendations. The midwife is a key health professional to provide nutrition education for pregnant women. Thus, it is important to know in detail her role in this respect. Aim: To explore how Spanish midwives undertake nutrition education in order to assess the need for specific interventions aimed at improving the health of pregnant women. Methods: A cross-sectional descriptive observational study was undertaken using an online questionnaire (466 responses). Findings: Spanish midwives recognise the importance of nutrition in pregnancy and that advising pregnant women in this regard is part of their role. In fact, all community midwives discuss nutrition to pregnant women, although they recognise that they do not feel particularly comfortable in dealing with certain topics, which could be related to a lack of mastery of the subjects. Midwives (56.5 %) rated the nutrition training their received as poor. Conclusion: In order to guarantee the quality in the nutrition education provided by Spanish midwives to promote the health of pregnant women, our results demonstrate the importance of strengthening both the nutrition content of midwives' training programmes and the ongoing support they receive throughout their professional life
Experimental study and geometrical method to design bio-inspired robotic kinematic chains of inching-locomotion caterpillars
No full textInching-locomotion caterpillars (ILAR) show impressive environmental adaptation, having high dexterity and flexibility. To design robots that mimic these abilities, a novel Bioinspired Robotic Design (BIROD) method is presented. The method is composed by an algorithm for Geometrical Kinematic Analysis (GEKINS) to standardize the proportional dimensions according to the insect’s anatomy and obtain the kinematic chains. The approach is experimentally applied to analyze the locomotion and kinematic chain of these specimens: Geometridae – 2 pair of prolegs (represents 35,000 species) and Plusiinae – 3 pair of prolegs (represents 400 species). The obtained data indicate that the application of the proposed method permits to locate the attachment mechanisms, joints, links, and to calculate angular displacement, angular average velocity, number of degrees of freedom, and thus the kinematic chain. Geometridae in contrast to Plusiinae, shows a longer Walk-Stride Length (WSL), a lower number of single-rotational joints in 2-D (3 DOF versus 4 DOF), and a lower number of dual-rotational joints in 3-D (6 DOF versus 8 DOF). The application of BIROD and GEKINS provides the forward kinematics for 35,400 ILAR species and are expected to be useful as a preliminary phase for the design of bio-inspired arthropod robots
Departamentos de la Universidad de Burgos a 1/1/2023
No full textDatos institucionales en abierto sobre los departamentos de la Universidad de Burgos. Datos actualizados a 1 de enero de 2023. Codificaciones de acuerdo con el Sistema Integrado de Información Universitaria (SIIU
Másteres ofertados por la Universidad de Burgos a 1/1/2023
No full textDatos institucionales en abierto sobre las titulaciones de Máster Universitario ofertadas por la Universidad de Burgos. Datos actualizados a 1 de enero de 2023. Codificaciones de acuerdo con el Sistema Integrado de Información Universitaria (SIIU)
Educación en sexualidad integral
No full textTrabajo realizado por alumnos del IES Félix Rodríguez de la FuenteEste trabajo consiste en una presentación de power point para intervenciones en educación sexual
Faraday rotation and transmittance as markers of topological phase transitions in 2D materials
No full textWe analyze the magneto-optical conductivity (and related magnitudes like transmittance and Faraday rotation of the irradiated polarized light) of some elemental two-dimensional Dirac materials of group IV (graphene analogues, buckled honeycomb lattices, like silicene, germanene, stannane, etc.), group V (phosphorene), and zincblende heterostructures (like HgTe/CdTe quantum wells) near the Dirac and gamma points, under out-of-plane magnetic and electric fields, to characterize topological-band insulator phase transitions and their critical points. We provide plots of the Faraday angle and transmittance as a function of the polarized light frequency, for different external electric and magnetic fields, chemical potential, HgTe layer thickness and temperature, to tune the material magneto-optical properties. We have shown that absortance/transmittance acquires extremal values at the critical point, where the Faraday angle changes sign, thus providing fine markers of the topological phase transition. In the case of non-topological materials as phosphorene, a minimum of the transmittance is also observed due to the energy gap closing by an external electric field.Funding information We thank the support of Grant PID2022-138144NB-I00 funded by Spanish MICIU and Junta de Andalucía through the projects FEDER/UJA-1381026 and FQM381. AM thanks the Spanish MIU for the FPU19/06376 predoctoral fellowship. OC is on sabbatical leave at Granada University, Spain, since the 1st of September 2023. OC thanks support from the program PASPA from DGAPA-UNAM