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1. Ultra Thin 3D Silicon Detector for Plasma Diagnostics at the ITER Tokamak

Author

Garcia, F., Pellegrini, G., Lozano, M., Balbuena, J. P., Fleta, C., Guardiola, C., and Quirion, D.

Subjects
Physics - Instrumentation and Detectors
Abstract

An ultra thin silicon detector called U3DTHIN has been designed and built for neutral particle analyzers (NPA) and thermal neutron detection. The main purpose of this detector is to provide a state-of-the-art solution for detector system of NPAs for the ITER experimental reactor and to be used in combination with a Boron conversion layer for the detection of thermal neutrons. Currently the NPAs are using very thin scintillator - photomultiplier tube, and their main drawbacks are poor energy resolution, intrinsic scintillation nonlinearity, relative low count rate capability and finally poor signal to background discrimination power for the low energy channels. The proposed U3DTHIN detector is based on very thin sensitive substrate which will provide nearly 100% detection efficiency for ions and at the same time very low sensitivity for the neutron and gamma radiation. To achieve a very fast charge collection of the carriers generated by the ions detection a 3D electrode structure[5] has been introduced in the sensitive volume of the detector. One of the most innovative features of these detectors has been the optimal combination of the thin entrance window and the sensitive substrate thickness, to accommodate very large energy dynamic range of the detected ions. An entrance window with a thickness of tens of nanometers together with a sensitive substrate thickness varying from less than 5 microns, to detect the lowest energetic ions to 20 microns for the height ones has been selected after simulations with GEANT4. To increase the signal to background ratio the detector will operate in spectroscopy regime allowing to perform pulse-height analysis. The technology used to fabricate these 3D ultra thin detectors developed at Centro Nacional de Microelectronica in Barcelona and the first signals from an alpha source (241Am) will presented

Published
2016
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5. Seasonal controlling factors of CO2 exchange in a semiarid shrubland in the Chihuahuan Desert, Mexico

Author

Flores-Rentería, D., Delgado-Balbuena, J., Campuzano, E.F., Curiel Yuste, J., Flores-Rentería, D., Delgado-Balbuena, J., Campuzano, E.F., and Curiel Yuste, J.

Abstract

The still significant uncertainties associated with the future capacity of terrestrial systems to mitigate climate change are linked to the lack of knowledge of the biotic and abiotic processes that regulate CO2 net ecosystem exchange (NEE) in space/time. Mainly, rates and controls of CO2 exchange from arid ecosystems, despite dominating the global trends in interannual variability of the terrestrial CO2 sink capacity, are probably the most poorly understood of all. We present a study on rates and controls of CO2 exchange measured with the eddy covariance (EC) technique in the Chihuahuan Desert in the Northeast of Mexico, to understand how the environmental controls of the NEE switch throughout the year using a multilevel approach. Since this is a water-limited ecosystem, the hydroecological year, based on the last precipitation and the decay of air temperature, was used to compare the wet (from May 16 to October 30, 2019) and dry (November 1, 2019 to May 15, 2020) seasons' controlling mechanisms, both at diurnal and nocturnal times. Annual NEE was −303.5 g C m−2, with a cumulative Reco of 537.7 g C m−2 and GPP of 841.3 g C m−2. NEE showed radiation, temperature, and soil moisture sensitivity along the day, however, shifts in these controls along the year and between seasons were identified. The winter precipitations during the dry season led to fast C release followed by lagged C uptake. Despite this flux pulse, the ecosystem was a net sink throughout most of the year because the local vegetation is well adapted to grow and uptake C under these arid conditions, even during the dry season. Understanding the controls of the sink-source shifts is relevant since the predictions for future climate include changes in the precipitation patterns. © 2022 Elsevier B.V.

Published
2023

13. 3D silicon pixel sensors: Recent test beam results

Author

Hansson, P., Balbuena, J., Barrera, C., Bolle, E., Borri, M., Boscardin, M., Chmeissan, M., Dalla Betta, G.-F., Darbo, G., Da Via, C., Devetak, E., DeWilde, B., Su, D., Dorholt, O., Fazio, S., Fleta, C., Gemme, C., Giordani, M., Gjersdal, H., Grenier, P., Grinstein, S., Hasi, J., Helle, K., Huegging, F., Jackson, P., Kenney, C., Kocian, M., Korolkov, I., La Rosa, A., Mastroberardino, A., Micelli, A., Nellist, C., Nordahl, P., Rivero, F., Rohne, O., Sandaker, H., Silverstein, D., Sjoebaek, K., Slaviec, T., Stupak, J., Troyano, I., Tsung, J., Tsybychev, D., Wermes, N., and Young, C.

Published
2011
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16. Multiscale modelling for fusion and fission materials: the M4F project

Author

Malerba, L., Caturla, M. J., Gaganidze, E., Kaden, C., Konstantinović, M. J., Olsson, P., Robertson, C., Rodney, D., Ruiz-Moreno, A. M., Serrano, M., Aktaa, J., Anento, N., Austin, S., Bakaev, A., Balbuena, J. P., Bergner, F., Boioli, F., Boleininger, M., Bonny, G., Castin, N., Chapman, J. B. J., Chekhonin, P., Clozel, M., Devincre, B., Dupuy, L., Diego, G., Dudarev, S. L., Fu, C. C., Gatti, R., Gélébart, L., Gómez-Ferrer, B., Gonçalves, D., Guerrero, C., Gueye, P. M., Hähner, P., Hannula, S. P., Hayat, Q., Hernández-Mayoral, M., Jagielski, J., Jennett, N., Jiménez, F., Kapoor, G., Kraych, A., Khvan, T., Kurpaska, L., Kuronen, A., Kvashin, N., Libera, O., Ma, P. W., Manninen, T., Marinica, M. C., Merino, S., Meslin, E., Mompiou, F., Mota, F., Namburi, H., Ortiz, C. J., Pareige, C., Prester, M., Rajakrishnan, R. R., Sauzay, M., Serra, A., Simonovski, I., Soisson, F., Spätig, P., Tanguy, D., Terentyev, D., Trebala, M., Trochet, M., Ulbricht, A., Vallet, M., Vogel, K., Yalcinkaya, T., Zhao, J., Malerba, L., Caturla, M. J., Gaganidze, E., Kaden, C., Konstantinović, M. J., Olsson, P., Robertson, C., Rodney, D., Ruiz-Moreno, A. M., Serrano, M., Aktaa, J., Anento, N., Austin, S., Bakaev, A., Balbuena, J. P., Bergner, F., Boioli, F., Boleininger, M., Bonny, G., Castin, N., Chapman, J. B. J., Chekhonin, P., Clozel, M., Devincre, B., Dupuy, L., Diego, G., Dudarev, S. L., Fu, C. C., Gatti, R., Gélébart, L., Gómez-Ferrer, B., Gonçalves, D., Guerrero, C., Gueye, P. M., Hähner, P., Hannula, S. P., Hayat, Q., Hernández-Mayoral, M., Jagielski, J., Jennett, N., Jiménez, F., Kapoor, G., Kraych, A., Khvan, T., Kurpaska, L., Kuronen, A., Kvashin, N., Libera, O., Ma, P. W., Manninen, T., Marinica, M. C., Merino, S., Meslin, E., Mompiou, F., Mota, F., Namburi, H., Ortiz, C. J., Pareige, C., Prester, M., Rajakrishnan, R. R., Sauzay, M., Serra, A., Simonovski, I., Soisson, F., Spätig, P., Tanguy, D., Terentyev, D., Trebala, M., Trochet, M., Ulbricht, A., Vallet, M., Vogel, K., Yalcinkaya, T., and Zhao, J.

Abstract

The M4F project brings together the fusion and fission materials communities working on the prediction of radiation damage production and evolution and its effects on the mechanical behaviour of irradiated ferritic/martensitic (F/M) steels. It is a multidisciplinary project in which several different experimental and computational materials science tools are integrated to understand and model the complex phenomena associated with the formation and evolution of irradiation induced defects and their effects on the macroscopic behaviour of the target materials. In particular the project focuses on two specific aspects: (1) To develop physical understanding and predictive models of the origin and consequences of localised deformation under irradiation in F/M steels; (2) To develop good practices and possibly advance towards the definition of protocols for the use of ion irradiation as a tool to evaluate radiation effects on materials. Nineteen modelling codes across different scales are being used and developed and an experimental validation programme based on the examination of materials irradiated with neutrons and ions is being carried out. The project enters now its 4th year and is close to delivering high-quality results. This paper overviews the work performed so far within the project, highlighting its impact for fission and fusion materials science.

Published
2021

29. Preparación de nuevos materiales fotocatalizadores para la descontaminación de gases NOx

Author

Balbuena, J., Sánchez Granados, Luis, and Cruz-Yusta, M.

Subjects
Nanotecnología, Óxidos de nitrógeno, Degradación fotocatalítica, Fotocatalizadores, Nanocomposites, Gases NOx
Abstract

El desarrollo del presente trabajo de investigación ha permitido alcanzar las siguientes conclusiones generales. a) En lo que respecta al diseño de nuevos materiales fotocatalizadores avanzados: - Se demuestra la capacidad de la fase hematita del óxido de hierro, -Fe2O3, como fotocatalizador eficiente para la degradación de gases NOx. - Se ha confirmado que el mecanismo fotocatalítico De-NOx conlleva el siguiente proceso de foto-oxidación: NO NO2 NO3 - No obstante, y a pesar de su tamaño nanométrico, la eficiencia fotocatalítica de la hematita resulta ser pobre. - La eficiencia fotocatalítica de la fase hematita se mejora al incrementar su superficie específica. En este sentido, estructuras unidimensionales constituidas por nanohilos nanocristalinos muestran una mejorada actividad De-NOX. - La fase α-Fe2O3 se puede preparar por la técnica CVD con un control efectivo de su nano-organización estructural. De igual modo se pueden preparar depósitos de α-Fe2O3/TiO2 nanoestructurados. La fase α-Fe2O3 actúa en sinergia con la fase anatasa del TiO2 obteniendo unas láminas delgadas muy eficientes en el proceso De-NOX. - Se demuestra que la actividad De-NOX de la fase TiO2 anatasa puede ser mejorada. La preparación de una estructura mesoporosa nanoparticulada conlleva a la obtención de un óxido TiO2 no sólo activo a la luz UV sino también en el Visible, además de una sobresaliente mejora en la selectividad del proceso fotoquímico. b) Por otra parte, en relación al estudio de nuevos materiales fotocatalíticos obtenidos a partir de residuos sólidos procedentes de otras industrias: - Se ha demostrado que se pueden realizar transformaciones adecuadas de los residuos industriales que les aporten un nuevo valor añadido y propiedades para la mejora de la calidad medioambiental. - Se ha optimizado el proceso de transformado de un residuo industrial en agente fotocatalizador. - Los residuos ricos en hierro son utilizados eficazmente como aditivos fotocatalizadores en materiales de construcción para aplicaciones de auto-limpieza y descontaminación de gases NOx. - En los materiales de construcción que además de incorporar los residuos transformados también incorporan TiO2, se observa una acción sinérgica de ambos aditivos fotocatalizadores que conduce a una clara mejora de la eficiencia fotocatalítica última del material. - Se ha demostrado que las cenizas de procedentes de la combustión de la cascarilla de arroz sirven de soporte útil de material fotocatalizador. - El proceso térmico de preparación de composites Fe2O3/SiO2 condiciona la morfología de la fase hematita soportada, así como su superficie específica. - Los composites Fe2O3/SiO2 presentan actividad De-NOX mejorada respecto a la observada para la muestra de hematite nanocristalina en polvo. Todas las conclusiones anteriores evidencian que se pueden preparar nuevos materiales con propiedades fotocatalíticas mejoradas en lo que respecta a la eliminación de gases NOX en atmósferas contaminadas, objetivo principal planteado al iniciar esta Tesis Doctoral.

Published
2017

33. Study of NOx abatement by calcium alumniate cements modified by TiO2

Author

Navarro-Blasco, I. (Iñigo), Cruz-Yusta, M. (Manuel), Balbuena, J. (José), Fernandez-Alvarez, J.M. (José María), Perez-Nicolas, M. (María), Sanchez, L. (Luis), and Alvarez-Galindo, J.I. (José Ignacio)

Subjects
Photocatalytic activity, Calcium aluminate cement, SEM, TiO2, NOx, NO2 Abatement
Abstract

Different percentages of TiO2 (1 to 10 wt.%) were incorporated into two different Calcium Aluminate Cements (iron rich – d-CAC – and iron lean – w-CAC–) which were cured under two curing conditions. The mild hydrothermal curing condition 2 was chosen so as to resemble the natural ageing of aluminate cements in which hydrated hexagonal phases are converted into more stable cubic ones. Fresh and hardened state properties were studied. NOx removal under UV illumination was assessed in TiO2-bearing mortar samples. NO conversion values were higher in w-CAC than in d-CAC. Retention of NO2 in w-CAC samples was also more successful than in d-CAC samples due to the presence of ferrite in the latter ones. The presence of ferrite in d-CAC was established by XRD, SEM and EDAX. The interaction of ferrite phases with TiO2 was monitored in both types of mortars and different behaviours were observed. In the d-CAC, the incorporation of TiO2 results in the appearance of two new iron containing phases: namely pseudobrookite and in a lesser extent ilmenite, at the expense of brownmillerite. These new phases yielded in an improve photocatalytic efficiency of d-CAC in the visible region of spectrum, as proved by Methyl Orange degradation tests.

Published
2014

38. 3D silicon pixel sensors: Recent test beam results RID G-5156-2010

Author

Hansson, P., Balbuena, J., Barrera, C., Bolle, E., Borri, M., Boscardin, M., Chmeissan, M., Dalla Betta, G. -F., Darbo, G., Da Via, C., Devetak, E., Dewilde, B., Su, D., Dorholt, O., Fazio, S., Fleta, C., Gemme, C., Giordani, M., Gjersdal, H., Grenier, P., Grinstein, S., Hasi, J., Helle, K., Huegging, F., Jackson, P., Kenney, C., Kocian, M., Korolkov, I., La Rosa, A., Mastroberardino, A., Micelli, A., Nellist, C., Nordahl, P., Rivero, F., Rohne, O., Sandaker, H., Silverstein, D., Sjoebaek, K., Slaviec, T., Stupak, J., Troyano, I., Tsung, J., Tsybychev, D., Wermes, N., and Young, C.

Published
2011

48. Charge Collection Studies and Electrical Measurements of Heavily Irradiated 3D Double-Sided Sensors and Comparison to Planar Strip Detectors

Author

Bates, Richard L., primary, Parkes, C., additional, Rakotomiaramanana, Barinjaka, additional, Fleta, C., additional, Pellegrini, Giulio, additional, Lozano, M., additional, Balbuena, J. P., additional, Parzefall, Ulrich, additional, Koehler, M., additional, Breindl, M., additional, and Blot, X., additional

Published
2011
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