Hydrogenated amorphous silicon-based nanomaterials as alternative electrodes to graphite for lithium-ion batteries

Graphite is the material most used as an electrode in commercial lithium-ion batteries. On the other hand, it is a material with low energy capacity, and it is considered a raw critical material given its large volume of use. In the current energy context, we must promote the search for alternative materials based on elements that are abundant, sustainable and that have better performance for energy storage. We propose thin materials based on silicon, which has a storage capacity eleven times higher than graphite. Nevertheless, due to the high-volume expansion during lithiation, it tends to crack, limiting the life of the batteries. To solve this problem, hydrogenated amorphous silicon has been researched, in the form of thin film and nanostructures, since, due to its amorphous structure, porosity and high specific surface, it could better absorb changes in volume. These thin films were grown by plasma-enhanced chemical vapor deposition, and then the nanowires were obtained by chemical etching. The compositional variations of films deposited at different temperatures and the incorporation of dopants markedly influence the stability and longevity of batteries. With these optimized electrodes, we achieved batteries with an initial capacity of 3800 mAhg−1 and 82% capacity retention after 50 cyclesThis research has been funded by the Spanish of Ministry of Economy and Competitiveness under projects SCALED (PID2019-109215RB-C42/ https://scaled-project.com/, accessed on June 2020), NanoCat-Com (PID2021-124667OB-I00, accessed on September 2022) and by the European Project STORIES (LC-GD-9-1-2020-European Research Infrastructures capacities and services to address European Green Deal challenges /https://www.eera-energystorage.eu/stories.html, accessed on November 202

Graphene-based electrodes for silicon heterojunction solar cell technology

Transparent conductive electrodes based on graphene have been previously proposed as an attractive candidate for optoelectronic devices. While graphene alone lacks the antireflectance properties needed in many applications, it can still be coupled with traditional transparent conductive oxides, further enhancing their electrical performance. In this work, the effect of combining indium tin oxide with between one and three graphene monolayers as the top electrode in silicon heterojunction solar cells is analyzed. Prior to the metal grid deposition, the electrical conductance of the hybrid electrodes was evaluated through reflection-mode terahertz time-domain spectroscopy. The obtained conductance maps showed a clear electrical improvement with each additional graphene sheet. In the electrical characterization of the finished solar cells, this translated to a meaningful reduction in the series resistance and an increase in the devices’ fill factor. On the other hand, each additional sheet absorbs part of the incoming radiation, causing the short circuit current to simultaneously decrease. Consequently, additional graphene monolayers past the first one did not further enhance the efficiency of the reference cells. Ultimately, the increase obtained in the fill factor endorses graphene-based hybrid electrodes as a potential concept for improving solar cells’ efficiency in future novel designs.This research was funded by DIGRAFEN, grant number ENE2017–88065-C2-2-R. The APC was funded by the Ministry of Economy, Industry and Competitiveness from Spain. das-Nano and UPNA would also like to acknowledge the funding from the Government of Navarra and the European Regional Development Fund (ERDF), 2020 I + D projects: ref. 0011-1365-2020-000026 for das-Nano and ref. 0011-1365-2020-000045 for UPNA

Fischer-Tropsch synthesis in microchannels

Different metallic supports (aluminum foams of 40ppi, honeycomb monolith and micromonolith of 350 and 1180cpsi, respectively) have been loaded with a 20%Co-0.5%Re/γ-Al2O3 catalyst by the washcoating method. Layers of different thicknesses have been deposited onto the metallic supports. The catalytic coatings were characterized measuring their textural properties, adhesion and morphology. These structured catalysts have been tested in the Fischer-Tropsch synthesis (FTS) and compared with a microchannel block presenting perpendicular channels for reaction and cooling. The selectivity depends on the type of support used and mainly on the thickness of the layer deposited. In general, the C5+ selectivity decreased at increasing CO conversion for all of the systems (powder, monoliths, foams and microchannels block). On the other hand, the selectivity to methane increased with the thickness of the catalytic layer due to the higher effective H2/CO ratio over the active sites resulting from the higher diffusivity of H2 compared with CO in the liquid products filling the pores. The C5+ selectivity of the microchannels reactor is higher than that of the structured supports and the powder catalyst.Ministerio de Ciencia e Innovación MAT2006-12386-C05, ENE2009-14522-C0

Distribution of lesions in red and fallow deer naturally infected with Mycobacterium bovis

Wild deer have an important role in the epidemiology of bovine tuberculosis (bTB). The aims of this study were (1) to compare the pattern of lesions present in wild red (Cervus elaphus) and fallow (Dama dama) deer that were naturally infected with Mycobacterium bovis, and (2) to use this information to develop a sampling strategy for the isolation of M. bovis from the lymphoid tissues of the head of these animals. Culture of head lymphoid tissues demonstrated that 28 of 95 red deer and 22 of 100 fallow deer sampled were infected with M. bovis. Approx- imately 30% of each deer population had no gross lesions. Fallow deer were significantly more likely to have thoracic lesions than red deer. Lesions were observed in the retropharyngeal lymph nodes of 64% of the culture-positive red deer and 43% of the culture positive fallow deer. One third of the red deer, but none of the fallow deer, had well-encapsulated abscess lesions. There were no microscopical differences in the lesions in the lymph nodes of the red and fallow deer. Bacteriological culture from both the tonsil and retro- pharyngeal lymph nodes increased the rate of isolation of M. bovis by 22% over culture of the retropharyngeal lymph nodes alone in both species. These findings indicate that investigation of wild deer for bTB-compatible lesions should include examination of the medial retropharyngeal, left tracheobronchial, mediastinal, mesen- teric and ileocaecal lymph nodes. Sampling for bacteriological culture from head lymphoid tissues should be from the tonsil and the medial retropharyngeal lymph nodes. These protocols may prove useful in bTB surveil- lance and control in regions where wild deer contribute to the circulation of M. bovis.This study was funded by Consejería de Medio Ambiente, Junta de Andalucía. This is a contribution to CICYT – MEC research grant AGL2008-03875 and FEDER, and to EU grant TB-STEP 212414. Studies on diseases shared between domestic animals and wildlife are also supported by grants and contracts from INIA, Principado de Asturias, Castilla – La Mancha (GC-006), Ministerio de Medio Ambiente y Medio Rural y Marino (OAPN and SDGSPP), and Grupo Santander – Fundacion Marcelino Botin. MPM-H acknowledges a post doctoral contract from the Instituto de Salud Carlos III.Peer reviewe

Distribution of lesions in red and fallow deer naturally infected with Mycobacterium bovis

Wild deer have an important role in the epidemiology of bovine tuberculosis (bTB). The aims of this study were (1) to compare the pattern of lesions present in wild red (Cervus elaphus) and fallow (Dama dama) deer that were naturally infected with Mycobacterium bovis, and (2) to use this information to develop a sampling strategy for the isolation of M. bovis from the lymphoid tissues of the head of these animals. Culture of head lymphoid tissues demonstrated that 28 of 95 red deer and 22 of 100 fallow deer sampled were infected with M. bovis. Approx- imately 30% of each deer population had no gross lesions. Fallow deer were significantly more likely to have thoracic lesions than red deer. Lesions were observed in the retropharyngeal lymph nodes of 64% of the culture-positive red deer and 43% of the culture positive fallow deer. One third of the red deer, but none of the fallow deer, had well-encapsulated abscess lesions. There were no microscopical differences in the lesions in the lymph nodes of the red and fallow deer. Bacteriological culture from both the tonsil and retro- pharyngeal lymph nodes increased the rate of isolation of M. bovis by 22% over culture of the retropharyngeal lymph nodes alone in both species. These findings indicate that investigation of wild deer for bTB-compatible lesions should include examination of the medial retropharyngeal, left tracheobronchial, mediastinal, mesen- teric and ileocaecal lymph nodes. Sampling for bacteriological culture from head lymphoid tissues should be from the tonsil and the medial retropharyngeal lymph nodes. These protocols may prove useful in bTB surveil- lance and control in regions where wild deer contribute to the circulation of M. bovis.This study was funded by Consejería de Medio Ambiente, Junta de Andalucía. This is a contribution to CICYT – MEC research grant AGL2008-03875 and FEDER, and to EU grant TB-STEP 212414. Studies on diseases shared between domestic animals and wildlife are also supported by grants and contracts from INIA, Principado de Asturias, Castilla – La Mancha (GC-006), Ministerio de Medio Ambiente y Medio Rural y Marino (OAPN and SDGSPP), and Grupo Santander – Fundacion Marcelino Botin. MPM-H acknowledges a post doctoral contract from the Instituto de Salud Carlos III.Peer reviewe

Dissociable Effects of Executive Load on Perceived Exertion and Emotional Valence during Submaximal Cycling

Endurance physical exercise is accompanied by subjective perceptions of exertion (reported perceived exertion, RPE), emotional valence, and arousal. These constructs have been hypothesized to serve as the basis for the exerciser to make decisions regarding when to stop, how to regulate pace, and whether or not to exercise again. In dual physical-cognitive tasks, the mental (executive) workload generated by the cognitive task has been shown to influence these perceptions, in ways that could also influence exercise-related decisions. In the present work, we intend to replicate and extend previous findings that manipulating the amount of executive load imposed by a mental task, performed concomitantly with a submaximal cycling session, influenced emotional states but not perceived exertion. Participants (experienced triathletes) were asked to perform a submaximal cycling task in two conditions with different executive demands (a two-back version of the n-back task vs. oddball) but equated in external physical load. Results showed that the higher executive load condition elicited more arousal and less positive valence than the lower load condition. However, both conditions did not differ in RPE. This experimental dissociation suggests that perceived exertion and its emotional correlates are not interchangeable, which opens the possibility that they could play different roles in exercise-related decision-making.Spanish Ministry of Economy and Competitiveness (Secretaria de Estado de Investigacion, Desarrollo e Innovacion; Convocatoria 2017 de Proyectos I + D, de Retos a la Sociedad; Spain) DEP2017-89879-RSpanish Government (Ministerio de Economia y Competitividad, Secretaria de Estado de Investigacion, Desarrollo e Innovacion; Convocatoria 2017 de Proyectos I + D de Excelencia, Spain - Fondo Europeo de Desarrollo Regional, FEDER, European Union) PSI2017-85488-

Impact of graphene monolayer on the performance of non-conventional silicon heterojunction solar cells with MoOx hole-selective contact

In this work, a new design of transparent conductive electrode based on a graphene monolayer is evaluated. This hybrid electrode is incorporated into non-standard, high-efficiency crystalline silicon solar cells, where the conventional emitter is replaced by a MoOx selective contact. The device characterization reveals a clear electrical improvement when the graphene monolayer is placed as part of the electrode. The current–voltage characteristic of the solar cell with graphene shows an improved FF and Voc provided by the front electrode modification. Improved conductance values up to 5.5 mS are achieved for the graphene-based electrode, in comparison with 3 mS for bare ITO. In addition, the device efficiency improves by around 1.6% when graphene is incorporated on top. These results so far open the possibility of noticeably improving the contact technology of non-conventional photovoltaic technologies and further enhancing their performance.This research was funded by MCIN/AEI/10.13039/501100011033, grant numbers PID2019-109215RB-C41 and PID2019-109215RB-C42.Peer ReviewedPostprint (published version

Study of the Quaternary deposits of Los Aljezares Natural Site (Aspe, Alicante): first contributions

Este trabajo recoge la primera aportación del estudio multidisciplinar llevado a cabo en los depósitos cuaternarios del Paraje Natural Municipal de Los Aljezares (Aspe, Alicante). El paraje se localiza en un área deprimida rodeada por altos topográficos únicamente interrumpidos por la entrada y salida del río Vinalopó de N a S. Los depósitos cuaternarios presentan techos planos continuos dispuestos a una cota topográfica similar, lo que puede llevar a relacionarlos con terrazas fluviales del Vinalopó, sin embargo reflejan superficies de colmatación de una cuenca sedimentaria previa al encajamiento del río. Están constituidos por depósitos de gravas y arenas gruesas, y lutitas y arenas finas que representarían respectivamente facies proximales y distales de sistemas aluviales procedentes de los relieves circundantes, dejando en la zona central un área lacutre-palustre. Una prospección geoarqueológica reciente ha permitido constatar la presencia de industria lítica en estos depósitos, permitiendo atribuir una edad Pleistoceno superior al relleno de la cuenca. Se han podido establecer tres etapas en la configuración del paraje de Los Aljezares. Una primera etapa de carácter erosivo correspondería al desarrollo del paleo-relieve que generó la cuenca, la segunda a la sedimentación de los depósitos cuaternarios estudiados y la tercera al encajamiento del río Vinalopó.This work includes the first contributions of the multidisciplinary study carried out in the Quaternary deposits of Los Aljezares Natrual Site (Aspe, Alicante). This site is located in a depressed area surrounded by topographical elevations only interrupted by the entrenching of the Vinalopó River from N to S. The Quaternary deposits show continuous flat tops in similar topographic level, suggesting fluvial terraces of the Vinalopó River. However, this study has allowed us to associate these deposits with the filling of a sedimentary basin formed previously to the entrenching of the river. The Quaternary deposits consist of gravel and coarse sand, and lutites and fine sands that would respectively show proximal and distal facies of alluvial systems coming from the surrounding reliefs, and leaving in the central area a lacustrine-palustrine zone. Additionally, lithic industry has been identified in these deposits in a recent geoarchaeological survey, allowing us to attribute them to a Upper Pleistocene age. Moreover, three stages in the configuration of Los Aljezares Natural Site have been established: i) a first erosional stage leaving the paleorelief where the basin is developed; ii) the sedimentation of the Quaternary deposits and iii) the entrenching of the Vinalopó River.Este estudio ha sido financiado a través de las actividades de investigación de la Asociación Cinco Ojos. Observatorio de Patrimonio y del convenio AYTOASPE1-16TPA entre la Universidad de Alicante y el Ayuntamiento de Aspe

Estudio de los depósitos cuaternarios del Paraje Natural Municipal de Los Aljezares (Aspe, Alicante): primeras aportaciones

Este trabajo recoge la primera aportación del estudio multidisciplinar llevado a cabo en los depósitos cuaternarios del Paraje Natural Municipal de Los Aljezares (Aspe, Alicante). El paraje se localiza en un área deprimida rodeada por altos topográficos únicamente interrumpidos por la entrada y salida del río Vinalopó de N a S. Los depósitos cuaternarios presentan techos planos continuos dispuestos a una cota topográfica similar, lo que puede llevar a relacionarlos con terrazas fluviales del Vinalopó, sin embargo reflejan superficies de colmatación de una cuenca sedimentaria previa al encajamiento del río. Están constituidos por depósitos de gravas y arenas gruesas, y lutitas y arenas finas que representarían respectivamente facies proximales y distales de sistemas aluviales procedentes de los relieves circundantes, dejando en la zona central un área lacutre-palustre. Una prospección geoarqueológica reciente ha permitido constatar la presencia de industria lítica en estos depósitos, permitiendo atribuir una edad Pleistoceno superior al relleno de la cuenca. Se han podido establecer tres etapas en la configuración del paraje de Los Aljezares. Una primera etapa de carácter erosivo correspondería al desarrollo del paleo-relieve que generó la cuenca, la segunda a la sedimentación de los depósitos cuaternarios estudiados y la tercera al encajamiento del río Vinalopó