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Characterization of Lime Mortar and Brick Used in an XVI Century Cistern. Case: Order of Santo Domingo Convent in Dominican Republic
No full text12 pages . -- Florence Heri-Tech 2024 . -- Part of the book series: Springer Proceedings in Materials (SPM,volume 70)With the arrival of the Europeans to America and the evangelizing project, the convents and monasteries arrived. Since most of them were on the outskirts of the cities and the religious lived in them, they needed water storage, using cisterns for this purpose. This research aims to characterize the lime mortar and brick used in the cistern of Santo Domingo Convent, built at the beginning of the 16th century in Hispaniola Island. Two mortar samples and one brick sample were taken to analyze in laboratory using X-Ray Diffraction (XRD), Differential Thermal and Thermogravimetric Analysis (DTA/TG), X-Ray Fluorescence (XRF), and Fourier-Transform Infrared Spectroscopy (FTIR). The research finding indicates that we have two types of mortars, one in which the binder is lime (60%) and calcium silicate hydrate probably formed by a pozzolanic reaction to reduce the porosity and increase the hydraulicity of the mortar. In the other mortar the binder, in addition to lime (15%), has another component that is silicon, iron, aluminum mineral.This research is funding by project “Development of a lime mortar for plastering with fungicidal and biocidal characteristics”, MorCal, Code: 2020-2021-3B1-205, funded by FONDOCyT 2020, MESCyT.Peer reviewe
Computational and experimental insights into single-atom catalysts supported on g-C<inf>3</inf>N<inf>4</inf>: Unraveling the superior stability and catalytic activity of Rh in hydroformylation reactions
No full textSingle-atom catalysts (SACs) have emerged as a promising class of materials, leveraging the benefits of both homogeneous and heterogeneous catalysis to enhance efficiency and selectivity. In this work we have investigated the catalytic performance of SACs supported on graphitic carbon nitride (g-C3N4) for hydroformylation reactions. A systematic evaluation of nine transition metal SACs (Fe, Ru, Os, Co, Rh, Ir, Ni, Pd, and Pt) anchored on g-C3N4 was conducted using a combination of Density Functional Theory (DFT) calculations and experimental validation. Computational results indicate that at higher metal loadings, most metal atoms tend to migrate into the interlayers of g-C3N4, reducing their accessibility to reactant species and limiting their involvement in the catalytic process. However, Ru, Os, Ir, and Co single atoms remain stabilized on the heptazine rings, residing on the outermost layer and preserving active sites, albeit with lower predicted catalytic activity compared to Rh, while Fe, Ni, Pd, and Pt preferentially localize within the interlayers. Ru, Rh, and Co SACs anchored on g-C3N4 were experimentally synthesized and characterized using Transmission Electron Microscopy (TEM), X-ray Photoelectron Spectroscopy (XPS), and in situ Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS), along with catalytic testing, confirming the single-atom nature of the catalysts and corroborating the theoretical findings.We would like to acknowledge Paula Sabaté-Fàbregas for her expert contribution in generating the plots, which significantly improved the clarity and presentation of our results. This work was supported by the Ministerio de Ciencia e Innovación (PID2021-127423NB-I00 project) and the Generalitat de Catalunya (Project 2021-SGR-623). A.P. is a Serra Húnter Fellow and ICREA Academia Prize 2019. We thank the Spanish Ministerio de Universidades for the predoctoral fellowship FPU20/00707 to R.M.-C. M.G. thanks for being funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) - 217133147/SFB1073, project C03. This work was supported by the CNRS, which we gratefully acknowledge. The authors acknowledge the financial support from EMERGENCE@INC2021. The authors acknowledge the financial support from the Japan Society for the Promotion of Science (JSPS) for Hiroya Ishikawa grant. R. Castaing characterization platform in Toulouse is also acknowledged. Computational time at the MARENOSTRUM supercomputer has been provided by the Barcelona Supercomputing Centre through a grant from Red Española de Supercomputación, projects QHS-2022-3-0028, QHS-2023-1-0012, and QHS-2024-1-0041.Peer reviewe
Facile integration of single-crystalline phthalocyanine nanowires and nanotrees as photo-enhanced conductometric sensors
No full textChemicals and CAS Registry Numbers
oxygen
7782-44-7
phthalocyanine
574-93-6This article is part of the themed collection: Synthesis, physical properties and applications of advanced nanocrystalline materialsThis article presents a reproducible and affordable methodology for fabricating organic nanowires (ONWs) and nanotrees (ONTs) as light-enhanced conductometric O2 sensors. This protocol is based on a solventless procedure for the formation of high-density arrays of nanowires and nanotrees on interdigitated electrodes. The synthesis combines physical vapour deposition for the self-assembled growth of free-phthalocyanine nanowires and soft plasma etching to prompt the nucleation sites on the as-grown ONWs to allow for the formation of nanotrees. Electrical conductivity in such low-dimensional electrodes was analysed in the context of density, length, and interconnection between nanowires and nanotrees. Furthermore, the electrodes were immersed in water to improve the nanowires' connectivity. The response of the nanotrees as conductometric O2 sensors was tested at different temperatures (from room temperature to 100 °C), demonstrating that the higher surface area exposed by the nanotrees, in comparison with that of their polycrystalline thin film counterparts, effectively enhances the doping effect of oxygen and increases the response of the ONT-based sensor. Both organic nanowires and nanotrees were used as model systems to study the augmented response of the sensors provided by illumination with white or monochromatic light to organic semiconducting systems. Interestingly, the otherwise negligible sensor response at room temperature can be activated (On/Off) under LED illumination, and no dependency on the illumination wavelength in the visible range was observed. Thus, under low-power LED illumination with white light, we show a response to O2 of 16% and 37% in resistivity for organic nanotrees at room temperature and 100 °C, respectively. These results open the path to developing room temperature long-lasting gas sensors based on one- and three-dimensional single-crystalline small-molecule nanowires.The authors thank the projects PID2022-143120OB-I00, TED2021-130916B-I00, and PCI2024-153451 funded by MCIN/AEI/10.13039/501100011033 and “ERDF (FEDER)” A way of making Europe, Fondos NextgenerationEU and Plan de Recuperación, Transformación y Resiliencia. Project ANGSTROM was selected in the Joint Transnational Call 2023 of M-ERA.NET 3, which is an EU-funded network of about 49 funding organisations (Horizon 2020 grant agreement No 958174). The project leading to this article has received funding from the EU H2020 program under grant agreement 851929 (ERC Starting Grant 3DScavengers).Peer reviewe
Incorporating thermal co-evaporation in current-matched all-perovskite triple-junction solar cells
No full textThermal co-evaporation of halide perovskites is a solution-free, conformal, scalable, and controllable deposition technique with great potential for commercial applications, particularly in multi-junction solar cells. Monolithic triple-junction perovskite solar cells have garnered significant attention because they can achieve very high efficiencies. Nevertheless, challenges arise in fabricating these devices, as they require multiple layers and precise current matching across complex absorber stacks. Here we demonstrate a current-matched monolithic all-perovskite p-i-n triple-junction solar cell enabled by controlled thermal co-evaporation of various absorber layers in the stack. The top and middle subcells were fabricated by developing optimized thermally co-evaporated Cs0.3FA0.7Pb(I0.56Br0.44)3 (1.80 eV bandgap) and FAPbI3 (1.53 eV) perovskites, respectively, while the bottom subcell employed a solution-processed Cs0.25FA0.75Pb0.5Sn0.5I3 (1.25 eV) perovskite. By optimising absorber thicknesses and compositions through optical modelling, we achieve excellent current matching between the top (9.6 mA cm-2), middle (9.3 mA cm-2), and bottom subcells (9.0 mA cm-2), achieving an overall efficiency of 15.8%. Optical modelling simulations suggest that current matching and efficiency up to 11.4 mA cm-2 and 37.6% respectively could be attainable using the latest interlayer materials. This work highlights the potential of scalable vapour-based deposition techniques for advancing multi-junction perovskite-based solar cells, paving the way for future developments in this field.The authors acknowledge the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program (HYPERION, grant agreement No. 756962), Cambridge Royce facilities grant EP/P024947/1, Sir Henry Royce Institute—recurrent grant EP/R00661X/1 with additional funding from the “Centre for Advanced Materials for Integrated Energy Systems (CAM-IES)” (EP/P007767/1), and the Engineering and Physical Sciences Research Council (EPSRC) (grant agreement No. EP/R023980/1, EP/T02030X/1 and EP/S030638/1, EP/V012932/1, and H2CAT). T. C.-J. Y acknowledges the support of the MSCA Individual Fellowship from the European Union's Horizon 2020 (PeTSoC, No. 891205). M. R. F. acknowledges funding from the EPSRC Centre for Doctoral Training in Connected Electronic and Photonic Systems (EP/S022139/1). G. V. and M. A. acknowledge the BBVA Foundation for their support through a Leonardo Fellowship. L. R., A. J.-S., S. C. P. and M. A. acknowledge grants TED2021-131001A-I00, CNS2022-135967, RYC2021-034941-I and PID2022-142525OA-I00 funded by MICIU/AEI/10.13039/501100011033, the European Union "NextGenerationEU"/PRTR and FEDER, EU. A. J.-S. gratefully acknowledges the Spanish Ministry of Universities for funding through a Beatriz Galindo Research fellowship BG20/00015. S. J. Z. acknowledges support from the Polish National Agency for Academic Exchange within the Bekker program (grant no. PPN/BEK/2020/1/00264/U/00001). Z. Y. O. acknowledges the scholarship from St John's College, University of Cambridge. J. F. O and C. D. acknowledge funding from the Engineering and Physical Sciences Research Council (EPSRC) Nano Doctoral Training Centre (EP/L015978/1). L. P. acknowledges funding from the Swiss National Science Foundation under the Early Postdoc. Mobility fellowship (P2ELP2_195109). Y.-H. C. acknowledges the Taiwan Cambridge Trust and Rank Prize fund. The authors would like to thank Alexander Ehm, Simon Kahmann, and Dietrich RT Zahn from the Institute of Physics, Chemnitz University of Technology, 09107 Chemnitz, Germany for support on ellipsometry characterisation of various samples. We thank Steve Haws for technical support with all the Royce Ambient Cluster related equipment and maintenance. For the purpose of open access, the authors have applied a Creative Commons Attribution (CC BY) license to any Author Accepted Manuscript version arising from this submission.Peer reviewe
Metal Doping Activation of Anion-Mediated Electron Transfer in Catalytic Reactions
No full textHeteroatom-doping has emerged as a transformative approach to producing high-performance catalysts, yet the current trial-and-error approach to optimize these materials remains ineffective. To enable the rational design of more efficient catalysts, models grounded in a deeper understanding of catalytic mechanisms are essential. Existing models, such as d-band center theory, fall short in explaining the role of dopants, particularly when these dopants do not directly interact with reactants. In this study, we synthesize various heteroatom-doped catalysts to explore the correlation between the electronic effects of the dopants and catalyst activity. Using Co-MoS2 as a model catalyst and the Li-S redox reaction within the cathode of Li-S batteries as a test system, we show the interaction between cobalt sites and adjacent lattice sulfur atoms disrupts the intrinsic structural and electronic symmetry of MoS2. This disruption enhances the transfer of spin-polarized electrons from metal centers to lattice sulfur and promotes the adsorption of reactant intermediates. Furthermore, by analyzing 20 different dopant elements, we establish a linear relationship between the electron density in the lattice sulfur and catalyst activity toward the reduction of sulfur species, a relationship that extends to other catalytic systems, such as the hydrogen evolution reaction.This work was financially supported by the SyDECat project from the Spanish MCIN/AEI/FEDER (PID2022-136883OB-C22), the 2BoSS project of the ERA-MIN3 program with the Spanish grant number PCI2022-132985/AEI/10.13039/501100011033, Generalitat de Catalunya 2021 SGR 01581 and 2021 SGR 00457 and European Union Next Generation EU/PRTR. This study is part of the Advanced Materials program and was supported by MCIN with funding from the European Union NextGenerationEU (PRTR-C17.I1) and by Generalitat de Catalunya. The authors thank the support from the project AMaDE (PID2023-149158OB-C43), funded by MCIN/AEI/10.13039/501100011033/ and by “ERDF A way of making Europe”, by the “European Union”. ICN2 is supported by the Severo Ochoa program from Spanish MCIN/AEI (Grant No.: CEX2021-001214-S) and is funded by the CERCA Programme/Generalitat de Catalunya. ICN2 acknowledges funding from Grant IU16-014206 (METCAM-FIB) funded by the European Union through the European Regional Development Fund (ERDF), with the support of the Ministry of Research and Universities, Generalitat de Catalunya. Authors acknowledge the use of funding from the State Investigation Agency, through the Severo Ochoa Programme for Centres of Excellence in R&D (CEX2023-001263-S) and “OXISOT” (PID2021-128410OB-I00). J.L. is grateful for the Natural Science Foundation of Sichuan project (2025ZNSFSC0139).With funding from the Spanish government through the "Severo Ochoa Centre of Excelence" accreditation (CEX2021-001214-S)With funding from the Spanish government through the "Severo Ochoa Centre of Excelence" accreditation (CEX2023-001263-S)Peer reviewe
Robust quantum engineering of current flow in carbon nanostructures at room temperature
No full textBottom-up on-surface synthesis enables the fabrication of carbon nanostructures with atomic precision. Good examples are graphene nanoribbons (GNRs), 1D conjugated polymers, and nanoporous graphenes (NPGs), which are gathering increasing attention for future carbon nanoelectronics. A key step is the ability to manipulate current flow within these nanomaterials. Destructive quantum interference (QI), long studied in the field of single-molecule electronics, has been proposed as the most effective way to achieve such control with molecular-scale precision. However, for practical applications, it is essential that such QI-engineering remains effective near or above room temperature. To assess this important point, here we combine large-scale molecular dynamics simulations and quantum transport calculations and focus our study on NPGs formed as arrays of laterally bonded GNRs. By considering various NPGs with different inter-GNR chemical connections we disentangle the different factors determining electronic transport in these carbon nanomaterials at 300 K. Our findings unequivocally demonstrate that QI survives at room temperature, with thermal vibrations weakly restricting current flow along GNRs while completely blocking transport across GNRs. Our results thus pave the way towards the future realization of QI-engineered carbon nanocircuitry operating at room temperature, which is a fundamental step towards carbon-based nanoelectronics and quantum technologies.G.C. acknowledges the project SAMOTHRACE “Sicilian micro and nanotechnology research and innovation centre” founded by PNRR-MUR (ECS_00000022, CUP B63C22000620005) for partial support. I.A. is grateful for a Juan de la Cierva postdoctoral grant (FJC2019-038971-I) from the Ministerio de Ciencia e Innovación (MCIN). O.K. is supported by the REDI Program, a project that has received funding from the European Union's Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement number 101034328. We thank the DTU Computing Center for HPC resources [52]. A.C. and S.R. acknowledge support from PID2019-106684GB-I00 also funded by MCIN/AEI/10.13039/501100011033/FEDER, UE, as well as PID2022-138283NB-I00 funded by MICIU/AEI/10.13039/501100011033 and SGR funded by Generalitat de Catalunya. ICN2 is funded by the CERCA Programme from Generalitat de Catalunya, and is currently supported by the Severo Ochoa Centres of Excellence programme, Grant CEX2021-001214-S, both funded by MCIN/AEI/10.13039.501100011033.With funding from the Spanish government through the "Severo Ochoa Centre of Excelence" accreditation (CEX2021-001214-S)Peer reviewe
New species of Galathea Fabricius, 1793 and Nanogalathea Tirmizi & Javed, 1980 (Crustacea: Decapoda, Galatheidae) from the Western Pacific
No full textSpecimens of squat lobsters belonging to the family Galatheidae, representing the genera Galathea and Nanogalathea, were collected during several cruises carried out in New Caledonia, Papua New Guinea, the Philippines and Phoenix Islands. The study of these specimens integrating molecular and morphological data revealed the presence of eight new species in Galathea and one in Nanogalathea. We describe and illustrate these new species. Molecular data from mitochondrial markers were also included to support the taxonomic status of the species. Finally, a key to species for the genus Galathea from the Indian and Pacific Oceans is also provided.Peer reviewe
Erosion of a dense molecular core by a strong outflow from a massive protostar
No full text[Context] Molecular outflows from massive protostars can impact the interstellar medium in different ways, adding turbulence on different spatial scales, dragging material at supersonic velocities, producing shocks and heating, and physically impinging onto dense structures that may be harboring other protostars.[Aims] We aim to quantify the impact of the outflow associated with the high-mass protostar GGD 27-MM2(E) on its parent envelope and how this outflow affects its environment.[Methods] We present Atacama Large Millimeter/submillimeter Array Band 3 observations of N2H+ (1–0) and CH3CN (5–4), as well as Band 7 observations of the H2CO molecular line emissions from the protostellar system GGD 27-MM2(E). Through position–velocity diagrams along and across the outflow axis, we studied the kinematics and structure of the outflow. We also fit extracted spectra of the CH3CN emission to obtain the physical conditions of the gas. We use the results to discuss the impact of the outflow on its surroundings.[Results] We find that N2H+ emission traces a dense molecular cloud surrounding GGD 27-MM2(E). We estimate that the mass of this cloud is ~13.3–26.5 M⊙. The molecular cloud contains an internal cavity aligned with the H2CO-traced molecular outflow. The outflow, also traced by CH3CN, shows evidence of a collision with a molecular core (MC), as indicated by the distinctive increases in the distinct physical properties of the gas such as the excitation temperature, column density, line width, and velocity. This collision results in an X-shaped structure in the northern part of the outflow around the position of the MC, which produces spray-shocked material downstream in the north of MC, as observed in position–velocity diagrams both along and across the outflow axis. The outflow has a mass of 1.7–2.1 M⊙, a momentum of 7.8–10.1 M⊙ km s−1, a kinetic energy of 5.0–6.6×1044 erg, and a mass-loss rate of 4.9–6.0×10−4 M⊙ yr−1.[Conclusions] The molecular outflow from GGD 27-MM2(E) significantly perturbs and erodes its parent cloud, compressing the gas of sources such as the MC and ALMA 12. The feedback from this powerful protostellar outflow helps maintain the turbulence in the surrounding area.We thank an anonymous referee for very useful suggestions that improved the presentation of this paper. We are indebted to Pablo Fonfría for his fruitful discussions and advices. J.A.L.V. and C.F.L. acknowledge grants from the National Science and Technology Council of Taiwan (NSTC 112–2112–M–001–039–MY3). M.F.L. acknowledges support from the European Research Executive Agency HORIZON-MSCA-2021-SE-01 Research and Innovation programme under the Marie Skłodowska-Curie grant agreement number 101086388 (LACEGAL). M.F.L. also acknowledges the warmth and hospitality of the ICE-UB group of star formation. S.C. acknowledges financial support from UNAM-PAPIIT IN107324, and CONACyT CF-2023-I-232 grants, México. J.M.G. and G.B. acknowledge support from the PID2020-117710GB-I00 and PID2023-146675NB-I00 grants funded by MCIN/ AEI /10.13039/501100011033. L.A.Z. acknowledges financial support from CONACyT-280775 and UNAM-PAPIIT IN110618, and IN112323 grants, México. R.G.M. acknowledges support from UNAM-PAPIIT project IN108822. This paper makes use of the following ALMA data: ADS/JAO.ALMA#2015.1.00480.S. ALMA is a partnership of ESO (representing its member states), NSF (USA) and NINS (Japan), together with NRC (Canada), NSTC and ASIAA (Taiwan), and KASI (Republic of Korea), in cooperation with the Republic of Chile. The Joint ALMA Observatory is operated by ESO, AUI/NRAO and NAOJ.Peer reviewe
Syn-tasiR-VIGS: a Novel Small RNA-Based Biotechnological Tool For Effective Gene Silencing in Plants.
No full textThe exploitation of mountain natural resources during the Iron Age in the Eastern Pyrenees: the case study of production unit G at Tossal de Baltarga (Bellver de Cerdanya, Lleida, Spain).
No full textThe Iron Age site of Tossal de Baltarga (Bellver de Cerdanya) was a large Iberian residential complex occupying a strategic position in the middle of the Eastern Pyrenees. It was destroyed by fire in the second half of the 3rd century BCE, preserving an important volume of archaeological and bioarchaeological material in certain areas. This is the case of Building G, a two-story construction whose violent blaze has offered the possibility of analyzing a precise moment in the history of an Iron Age productive unit. The existence of a stable on the lower floor, where four sheep, a goat, and a horse were documented, and an upper floor, where textile production and storage were evidenced, allows us to analyse the complexity of the economic activities and exploitation of local resources, such as livestock, agriculture, forestry and mining.Peer reviewe