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Special Issue “Applications of Artificial Intelligence Systems”
No full textArtículo editorialCITIC, as a Research Center of the University System of Galicia, is funded by Consellería de Educación, Universidade e Formación Profesional of the Xunta de Galicia through the European Regional Development Fund and the Secretaría Xeral de Universidades (ref. ED431G 2019/01)
Másteres ofertados por la Universidad de Burgos a 1/1/2022
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 2022. Codificaciones de acuerdo con el Sistema Integrado de Información Universitaria (SIIU)
Filtration of subcritical water hydrolysates from red macroalgae byproducts with ultraporous ceramic membranes for oligosaccharide and peptide fractionation
Get PDFAn ultrafiltration-based process for oligosaccharide and peptide fractionation from a macroalgae subcritical
water hydrolysate was studied. A wide range of separation results was obtained depending on the membrane
pore. 100 kDa cut-off size was enough for hydrolysate clarification with total retention of colloidal materials.
Oligosaccharides present in the hydrolysate showed the highest retention with all membranes, glucans mostly,
followed by galactans, and finally arabinans. Peptides obtained after subcritical water treatment were some of
the lowest rejected compounds, even using a 5 kDa membrane. The increase in temperature from 20 to 50 ◦C and
feed flow rate from 6.6 to 11.2 L/h enhanced permeate flux for 5 kDa membrane, without perturbing the
membrane retention. The Hermia’s models identified the cake layer resistance as the major fouling resistance in
hydrolysate filtrations at 20 ◦C, but standard pore blockage was the principal fouling mechanism at 50 ◦C. A
fractionation process with sequential filtration stages at 20 ◦C and TMP = 1.1 bar was examined. Oligosaccharides were fractionated in the retentates of the sequential filtrations with 100, 5 and 1 kDa membranes. The
final permeate collected from the 1 kDa membrane was freeze-dried to obtain a peptide-rich solid (71 wt%) that
could be used in different applications.The authors gratefully acknowledge the financial support provided by the Agencia Estatal de Investigación [grant number PID2019–104950RB-I00/AEI/10.13039/501100011033] and by the Junta de Castilla y León (JCyL) and the European Regional Development Fund (ERF) [grant number BU050P20]. E. Trigueros predoctoral contract was funded by the JCyL and the European Social Fund (ESF) by ORDEN EDU/574/2018
An international empirical study of greenwashing and voluntary carbon disclosure
Get PDFVoluntary corporate environmental disclosure has increased significantly in the last decade. However, the increase in environmental disclosure has also been accompanied by the social questioning of its veracity. Previous
studies have mainly focused on the determinant factors behind corporate decisions to disclose environmental
data, with only limited consideration of both carbon performance and the veracity of the information disclosed.
Based on an international sample of firms from 12 countries, this paper analyzes the impact of regulative
pressures related to climate change on the likelihood of companies engaging in greenwashing. The results show
that the number of regulations related to climate change negatively influences the propensity of firms to engage
in greenwashing. Furthermore, firms in countries with stringent climate-related regulations are less likely to
participate in greenwashing practices. This paper adds to the existing literature concerning greenwashing by
demonstrating that institutional theory can deliver further insights into the explanation of corporate greenwashing behavior. This is the first study to incorporate international climate-related regulations into the analysis
of corporate greenwashing. It also provides a new method for identifying greenwashing firms, based on their
carbon performance and disclosure.This study has been supported by the Universidad de Sevilla VI PPIT [IV.3, 2018]
Products released from surgical face masks can provoke cytotoxicity in the marine diatom Phaeodactylum tricornutum
Get PDFSurgical face masks are more present than ever as personal protective equipment due to the COVID-19 pandemic. In
this work, we show that the contents of regular surgical masks: i) polypropylene microfibres and ii) some added metals
such as: Al, Fe, Cu, Mn, Zn and Ba, may be toxic to some marine life. This work has got two objectives: i) to study the
release rate of the products from face masks in marine water and ii) to assess the toxicity in Phaeodactylum tricornutum
of these by-products. To achieve these two objectives, we performed release kinetic experiments by adding masks in
different stages of fragmentation to marine water (i.e. whole face masks and fragments of them 1.52 ± 0.86 mm). Released microfibres were found after one month in shaking marine water; 0.33 ± 0.24 and 21.13 ± 13.19 fibres·mL−1
were collected from the whole and fragmented face masks, respectively. Significant amounts of dissolved metals such
as Mn, Zn and Ni, as well as functional groups only in the water containing the face mask fragments were detected.
Water from both treatments was employed to study its toxicity on the marine diatom. Only the water from the face
mask fragments showed a significant, dose-dependent, decrease in cell density in P. tricornutum; 53.09 % lower than
in the controls. Although the water from the face mask fragments showed greater effects on the microalgae population
than the water from the whole face mask, the latter treatment did show significant changes in the photosynthetic apparatus and intrinsic properties of the cells. These results indicate that during fragmentation and degradation face
masks a significant chemical print can be observed in the marine environment.Marta Sendra wishes to acknowledge her contract Juan de la Cierva Incorporación (IJC2020-043162-I) funded by MCIN/AEI/10.13039/ 501100011033 and European Union NextGenerationEU/PRTR. Dr. Araceli Rodríguez-Romero is supported by the Spanish grant Juan de la Cierva Incorporación referenced as IJC2018–037545-I
Comparative Life Cycle Assessment (LCA) between standard gypsum ceiling tile and polyurethane gypsum ceiling tile
Get PDFIn this paper, the LCA of two gypsum ceiling tiles is compared, the first one is a traditional gypsum tile
and the second is a new eco ceiling tile in which polyurethane foam waste has been incorporated.
Both tiles were made at one of the largest gypsum tile factories in Europe. The life cycle assessment
has been considered from cradle to grave for which the corresponding production stages have been
defined. This includes the extraction and transportation of raw materials, the manufacturing process,
transportation to the client, the use of the product and the end of its useful life. The results show that
the tile with polyurethane has a better environmental performance than the standard commercial ceiling
tile. This is quantified as a 14% reduction in energy consumption, a 14% reduction in CO2 emissions and a
25% reduction in water consumption compared with the standard tile, all the while maintaining the technical performance. An analysis of the results suggests that the new eco product has a competitive advantage on the market thanks to its environmental improvements and good technical performance.This study was carried out within the framework of the LIFEREPOLYUSE Recovery of polyurethane for reuse in eco-efficient materials. LIFE 16 ENV/ES/000254 Project. LIFE 2016. Environment Life Programme. European Commission. The authors are also grateful to the BU070P20 Project funded by the Fondo Europeo de Desarrollo Regional (FEDER) of the EU and the Junta de Castilla y León (Spain). In addition, the authors are grateful to the European Social Fund (European Union) and the Education Board of the Junta de Castilla y León (Spain) for funding the investigation
Parameter Optimisation in Selective Laser Melting on C300 Steel
Get PDFAdditive manufacturing (AM) of metallic materials is increasingly being adopted in
numerous sectors, such as biomedicine, aerospace or automotive industries, due to its versatility
in the creation of complex geometries and the minimisation of material waste when compared to
traditional subtractive methods. In order to ensure a reliable operation of these parts, however, an
in-depth study of the effect of additive manufacturing on mechanical properties, including tensile,
fatigue and fracture resistance, is necessary. Among the vast number of methods and materials, this
project is focused in one of the most promising techniques for the industry: Selective Laser Melting
(SLM) for the production of a tools steel, in particular C300 steel components for the automotive sector.
The main objective of this paper is to optimise some of the key parameters in the printing process,
such as laser power, laser speed and hatch spacing. These variables are essential to obtain parts with
good resistance. To that purpose, tensile tests were performed in 3D printed specimens, and then
elastoplastic properties were extracted, organised and analysed through a design of experiments for
the subsequent output fitting using the response surface methodology.This research was funded by: INVESTUN/22/BU/0003 // BU-002-P20 // MU-21-UP2021-030
Modification of the mean free path of very high-energy photons due to a relativistic deformed kinematics
No full textUltra-high-energy physics is about to enter a new era thanks to the impressive results of experiments such as the Large
High Altitude Air Shower Observatory, detecting photons of up to 1.4 × 1015 eV (PeV scale). These new results could be used to
test deviations with respect to special relativity. While this has been already explored within the approach of Lorentz Invariance
Violation theories, in this work we consider, for the first time, modifications due to a relativistic deformed kinematics (which appear
in Doubly Special Relativity, or DSR, theories). In particular, we study the mean free path of very high-energy photons due to
electron-positron pair creation when interacting with low-energy photons of the cosmic microwave background. Depending on the
energy scale of the relativistic deformed kinematics, present (or near future) experiments can be sensitive enough to be able to
identify deviations from special relativity.This work is supported by Spanish Grants PGC2018-095328-B-I00 (FEDER/AEI), and DGIID-DGA No. 2015-E24/2. JJR acknowledges support from the INFN Iniziativa Specifica GeoSymQFT and Unión Europea-NextGenerationEU (“Ayudas Margarita Salas para la formación de jóvenes doctores”). The work of MAR was supported by MICIU/AEI/FSE (FPI Grant PRE2019-089024). This work has been partially supported by Agencia Estatal de Investigación (Spain) under Grant PID2019-106802GB-I00/AEI/10.13039/501100011033. The authors would like to acknowledge the contribution of the COST Action CA18108 “Quantum gravity phenomenology in the multi-messenger approach”