72 research outputs found
Relativistic correlation correction to the binding energies of the ground configuration of Beryllium-like, Neon-like, Magnesium-like and Argon-like ions
Total electronic correlation correction to the binding energies of the
isoelectronic series of Beryllium, Neon, Magnesium and Argon, are calculated in
the framework of relativistic multiconfiguration Dirac-Fock method. Convergence
of the correlation energies is studied as the active set of orbitals is
increased. The Breit interaction is treated fully self-consistently. The final
results can be used in the accurately determination of atomic masses from
highly charged ions data obtained in Penning-trap experiments.Comment: version soumise 3/08/200
A supramolecular keypad lock
The reversible photoswitching between an anthracene derivative and its [4+4] dimer, using the template effect of the CB8 macrocycle, was demonstrated. This example of supramolecular chemistry in water was harnessed to demonstrate the operation of a keypad lock device that is driven by means of light and chemicals as inputs
Novel effects of strains in graphene and other two dimensional materials
The analysis of the electronic properties of strained or lattice deformed
graphene combines ideas from classical condensed matter physics, soft matter,
and geometrical aspects of quantum field theory (QFT) in curved spaces. Recent
theoretical and experimental work shows the influence of strains in many
properties of graphene not considered before, such as electronic transport,
spin-orbit coupling, the formation of Moir\'e patterns, optics, ... There is
also significant evidence of anharmonic effects, which can modify the
structural properties of graphene. These phenomena are not restricted to
graphene, and they are being intensively studied in other two dimensional
materials, such as the metallic dichalcogenides. We review here recent
developments related to the role of strains in the structural and electronic
properties of graphene and other two dimensional compounds.Comment: 75 pages, 15 figures, review articl
Fundamental parameters related to selenium kα and kβ emission x-ray spectra
This research was funded in part by FCT (Portugal) under research center grants UID/FIS/04559/2020 (LIBPhys) and UID/MULTI/04046/2020 (BioISI). This work was also funded through the project PTDC/FIS-AQM/31969/2017, "Ultra-high-accuracy x-ray spectroscopy of transition metal oxides and rare earths." J.M. and J.P.S acknowledge the support of EMPIR, under Contract No. 17FUN02MetroMMC. The EMPIR initiative is co-funded by the European Union's Horizon 2020 research and innovation programme and the EMPIR participating States.We present relativistic ab initio calculations of fundamental parameters for atomic selenium, based on the Multiconfiguration Dirac-Fock method. In detail, fluorescence yields and subshell linewidths, both of K shell, as well as Kβ to Kα intensity ratio are provided, showing overall agreement with previous theoretical calculations and experimental values. Relative intensities were evaluated assuming the same ionization cross-section for the K-shell hole states, leading to a statistical distribution of these initial states. A method for estimating theoretical linewidths of X-ray lines, where the lines are composed by a multiplet of fine-structure levels that are spread in energy, is proposed. This method provides results that are closer to Kα1,2 experimental width values than the usual method, although slightly higher discrepancies occur for the Kβ1,3 lines. This indicates some inaccuracies in the calculation of Auger rates that have a higher contribution for partial linewidths of the subshells involved in the Kβ1,3 profile. Apart from this, the calculated value of Kβ to Kα intensity ratio, which is less sensitive to Auger rates issues, is in excellent agreement with recommended values.publishersversionpublishe
Effect of distance and daily periods on heat‐stressed pigs and pre‐slaughter losses in a semiarid region
K- and L-shell theoretical fluorescence yields for the Fe isonuclear sequence
Funding Information: This research was funded in part by FCT (Portugal) under research center grant UID/FIS/04559/2020 (LIBPhys). This work was also funded through the project PTDC/FIS-AQM/31969/2017, “Ultra-high-accuracy X-ray spectroscopy of transition metal oxides and rare earths”. F.G. acknowledges support from FCT, Portugal through contract UI/BD/151000/2021 . J. M and J.P.S acknowledge the support of EMPIR, Germany , under Contract No. 20FUN04 PrimA-LTD. The EMPIR initiative is co-funded by the European Union’s Horizon 2020 research and innovation programme and the EMPIR, Germany participating States. Part of this work has been carried out under the High Performance Computing Chair - a R&D infrastructure (based at the University of Évora; PI: M. Avillez), endorsed by Hewlett Packard Enterprise (HPE), and involving a consortium of higher education institutions (University of Algarve, University of Évora, NOVA University Lisbon, and University of Porto), research centres (CIAC, CIDEHUS, CHRC), enterprises (HPE, ANIET, ASSIMAGRA, Cluster Portugal Mineral Resources, DECSIS, FastCompChem, GeoSense, GEOtek, Health Tech, Starkdata), and public/private organizations (Alentejo Tourism-ERT, KIPT Colab). Funding Information: This research was funded in part by FCT (Portugal) under research center grant UID/FIS/04559/2020 (LIBPhys). This work was also funded through the project PTDC/FIS-AQM/31969/2017, “Ultra-high-accuracy X-ray spectroscopy of transition metal oxides and rare earths”. F.G. acknowledges support from FCT, Portugal through contract UI/BD/151000/2021. J. M and J.P.S acknowledge the support of EMPIR, Germany, under Contract No. 20FUN04 PrimA-LTD. The EMPIR initiative is co-funded by the European Union's Horizon 2020 research and innovation programme and the EMPIR, Germany participating States. Part of this work has been carried out under the High Performance Computing Chair - a R&D infrastructure (based at the University of Évora; PI: M. Avillez), endorsed by Hewlett Packard Enterprise (HPE), and involving a consortium of higher education institutions (University of Algarve, University of Évora, NOVA University Lisbon, and University of Porto), research centres (CIAC, CIDEHUS, CHRC), enterprises (HPE, ANIET, ASSIMAGRA, Cluster Portugal Mineral Resources, DECSIS, FastCompChem, GeoSense, GEOtek, Health Tech, Starkdata), and public/private organizations (Alentejo Tourism-ERT, KIPT Colab). Publisher Copyright: © 2022 The Author(s)In this work, we present K- and L- shell fluorescence yield values of the full isonuclear sequence of Fe ions, using a state-of-the-art multiconfiguration Dirac–Fock approach. These results may be of importance for spectral fitting and plasma modeling, both in laboratory and astrophysical studies, where Fe is an important benchmark element. The K-shell fluorescence yields were found to be very similar up to the removal of 14 electrons.publishersversionpublishe
L-alanyl-glutamine pretreatment attenuates acute inflammatory response in children submitted to palatoplasty
A photoinduced pH jump applied to drug release from cucurbit[7]uril
A proof-of-principle for the application of a photoinduced pH jump for delivery of the Hoechst 33258 drug by disassembly of its host-guest complex with cucurbit[7]uril is described
High-pressure balloon assessment of pelviureteric junction prior to laparoscopic “vascular hitch”
Reconstructing Three Decades of Land Use and Land Cover Changes in Brazilian Biomes with Landsat Archive and Earth Engine
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