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Artículos SCI



2023


Threads of memory: Reviving the ornament of a dead child at the Neolithic village of Ba`ja (Jordan)

Alarashi, H et al. [Aviles, MA]
Plos One, 18 (2023)

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In 2018, a well-constructed cist-type grave was discovered at Ba`ja, a Neolithic village (7,400-6,800 BCE) in Southern Jordan. Underneath multiple grave layers, an 8-year-old child was buried in a fetal position. Over 2,500 beads were found on the chest and neck, along with a double perforated stone pendant and a delicately engraved mother-of-pearl ring discovered among the concentration of beads. The first was found behind the neck, and the second on the chest. The meticulous documentation of the bead distribution indicated that the assemblage was a composite ornament that had gradually collapsed, partly due to the burying position. Our aim was to challenge time degradation and to reimagine the initial composition in order to best explore the significance of this symbolic category of material culture, not as mere group of beads, but as an ornamental creation with further aesthetic, artisanal and socioeconomic implications. The reconstruction results exceeded our expectations as it revealed an imposing multi-row necklace of complex structure and attractive design. Through multiple lines of evidence, we suggest that the necklace was created at Ba`ja, although significant parts of beads were made from exotic shells and stones, including fossil amber, an unprecedented material never attested before for this period. The retrieval of such an ornament from life and its attribution to a young dead child highlights the significant social status of this individual. Beyond the symbolic functions related to identity, the necklace is believed to have played a key role in performing the inhumation rituals, understood as a public event gathering families, relatives, and people from other villages. In this sense, the necklace is not seen as belonging completely to the realm of death but rather to the world of the living, materializing a collective memory and shared moments of emotions and social cohesion.


Agosto, 2023 | DOI: 10.1371/journal.pone.0288075

Materiales Ópticos Multifuncionales

Inkjet-Printed and Nanopatterned Photonic Phosphor Motifs with Strongly Polarized and Directional Light-Emission

Cabello-Olmo, E; Romero, M; Kainz, M; Bernroitner, A; Kopp, S; Muhlberger, M; Lozano, G; Miguez, H
Advanced Functional Materials, (2023) 2305907

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Herein a versatile and scalable method to prepare periodically corrugated nanophosphor surface patterns displaying strongly polarized and directional visible light emission is demonstrated. A combination of inkjet printing and soft lithography techniques is employed to obtain arbitrarily shaped light emitting motifs. Such predesigned luminescent drawings, in which the polarization and angular properties of the emitted light are determined and finely tuned through the surface relief, can be used as anti-counterfeiting labels, as these two specific optical features provide additional means to identify any unauthorized or forged copy of the protected item. The potential of this approach is exemplified by processing a self-standing photoluminescent quick response code whose emission is both polarized and directionally beamed. Physical insight of the mechanism behind the directional out-coupled photoluminescence observed is provided by finite-difference time-domain calculations.


Agosto, 2023 | DOI: DOI10.1002/adfm.202305907

Materiales Semiconductores para la Sostenibilidad

Surfactant-Dependent Bulk Scale Mechanochemical Synthesis of CsPbBr3 Nanocrystals for Plastic Scintillator-Based X-ray Imaging

Ghosh, J; O'Neill, J; Masteghin, MG; Braddock, I; Crean, C; Dorey, R; Salway, H; Anaya, M; Reiss, J; Wolfe, D; Sellin, P
ACS Applied Nano Materials,

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We report a facile, solvent-free surfactant-dependentmechanochemicalsynthesis of highly luminescent CsPbBr3 nanocrystals (NCs)and study their scintillation properties. A small amount of surfactantoleylamine (OAM) plays an important role in the two-step ball millingmethod to control the size and emission properties of the NCs. Thesolid-state synthesized perovskite NCs exhibit a high photoluminescencequantum yield (PLQY) of up to 88% with excellent stability. CsPbBr3 NCs capped with different amounts of surfactant were dispersedin toluene and mixed with polymethyl methacrylate (PMMA) polymer andcast into scintillator discs. With increasing concentration of OAMduring synthesis, the PL yield of CsPbBr3/PMMA nanocompositewas increased, which is attributed to reduced NC aggregation and PLquenching. We also varied the perovskite loading concentration inthe nanocomposite and studied the resulting emission properties. Themost intense PL emission was observed from the 2% perovskite-loadeddisc, while the 10% loaded disc exhibited the highest radioluminescence(RL) emission from 50 kV X-rays. The strong RL yield may be attributedto the deep penetration of X-rays into the composite, combined withthe large interaction cross-section of the X-rays with the high-Zatoms within the NCs. The nanocomposite disc shows an intense RL emissionpeak centered at 536 nm and a fast RL decay time of 29.4 ns. Further,we have demonstrated the X-ray imaging performance of a 10% CsPbBr3 NC-loaded nanocomposite disc.


Agosto, 2023 | DOI: 10.1021/acsanm.3c02531

Química de Superficies y Catálisis

H2-rich syngas production from biogas reforming: Overcoming coking and sintering using bimetallic Ni-based catalysts

Carrasco-Ruiz, S; Zhang, Q; Gándara-Loe, J; Pastor-Pérez, L; Odriozola, JA; Reina, TR; Bobadilla, LF
International Journal of Hydrogen Energy, 48 (2023) 72

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Dry reforming of methane is a very appealing catalytic route biogas (mainly composed by greenhouse gases: carbon dioxide and methane) conversion into added value syngas, which could be further upgraded to produce liquid fuels and added value chemicals. However, the major culprits of this reaction are coking and active phase sintering that result in catalysts deactivation. Herein we have developed a highly stable bimetallic Ni–Rh catalyst supported on mixed CeO2–Al2O3 oxide using low-noble metal loadings. The addition of small amounts of rhodium to nickel catalysts prevents coke formation and improves sintering resistance, achieving high conversions over extended reaction times hence resulting in promising catalysts for biogas upgrading.


Agosto, 2023 | DOI: 10.1016/j.ijhydene.2023.03.301

Materiales Ópticos Multifuncionales

Measurement principles for quantum spectroscopy of molecular materials with entangled photons

Moretti, L; Rojas-Gatjens, E; Uboldi, L; Tiede, DO; Kumar, EJ; Trovatello, C; Preda, F; Perri, A; Manzoni, C; Cerullo, G; Kandada, ARS
Journal of Chemical Physics, 159 (2023) 084201

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Nonlinear spectroscopy with quantum entangled photons is an emerging field of research that holds the promise to achieve superior signal-to-noise ratio and effectively isolate many-body interactions. Photon sources used for this purpose, however, lack the frequency tunability and spectral bandwidth demanded by contemporary molecular materials. Here, we present design strategies for efficient spontaneous parametric downconversion to generate biphoton states with adequate spectral bandwidth and at visible wavelengths. Importantly, we demonstrate, by suitable design of the nonlinear optical interaction, the scope to engineer the degree of spectral correlations between the photons of the pair. We also present an experimental methodology to effectively characterize such spectral correlations. Importantly, we believe that such a characterization tool can be effectively adapted as a spectroscopy platform to optically probe system-bath interactions in materials.


Agosto, 2023 | DOI: 10.1063/5.0156598

 

 

 

 

 

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