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Romanelli G, Andreani C, Bocedi A, Senesi R. Quantum motion of oxygen and hydrogen in water: Atomic and total kinetic energy across melting from neutron scattering measurements. J Chem Phys 2024; 160:234503. [PMID: 38884402 DOI: 10.1063/5.0211165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2024] [Accepted: 05/22/2024] [Indexed: 06/18/2024] Open
Abstract
We provide a concurrent measurement of the hydrogen and oxygen nuclear kinetic energies in the water molecule across melting at 270 K in the solid phase and 276 K in the liquid phase. Experimental values are obtained by analyzing the neutron Compton profiles of each atomic species in a deep inelastic neutron scattering experiment. The concurrent measurement of the atom kinetic energy of both hydrogen and oxygen allows the estimate of the total kinetic energy per molecule due to the motion of nuclei, specifically 35.3 ± 0.8 and 34.8 ± 0.8 kJ/mol for the solid and liquid phases, respectively. Such a small difference supports results from ab initio simulations and phenomenological models from the literature on the mechanism of competing quantum effects across the phase change. Despite the experimental uncertainties, the results are consistent with the trend from state-of-the-art computer simulations, whereby the atom and molecule kinetic energies in the liquid phase would be slightly lower than in the solid phase. Moreover, the small change of nuclear kinetic energy across melting can be used to simplify the calculation of neutron-related environmental dose in complex locations, such as high altitude or polar neutron radiation research stations where liquid water and ice are both present: for neutron energies between hundreds of meV and tens of keV, the total scattering cross section per molecule in the two phases can be considered the same, with the macroscopic cross section only depending upon the density changes of water near the melting point.
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Affiliation(s)
- Giovanni Romanelli
- Dipartimento di Fisica and NAST Centre, Università degli Studi di Roma "Tor Vergata," via della Ricerca Scientifica 1, 00133 Rome, Italy
| | - Carla Andreani
- Dipartimento di Fisica and NAST Centre, Università degli Studi di Roma "Tor Vergata," via della Ricerca Scientifica 1, 00133 Rome, Italy
| | - Alessio Bocedi
- Dipartimento di Scienze e Tecnologie Chimiche and NAST Centre, Università degli Studi di Roma "Tor Vergata," via della Ricerca Scientifica 1, 00133 Rome, Italy
| | - Roberto Senesi
- Dipartimento di Fisica and NAST Centre, Università degli Studi di Roma "Tor Vergata," via della Ricerca Scientifica 1, 00133 Rome, Italy
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Romanelli G, Capuani S, Onorati D, Ulpiani P, Preziosi E, Andreani C, Senesi R. Fluorinated borono-phenylalanine for optimizing BNCT: Enhancing boron absorption against hydrogen scattering for thermal neutrons. Med Phys 2024; 51:439-446. [PMID: 37956252 DOI: 10.1002/mp.16802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Revised: 06/14/2023] [Accepted: 07/16/2023] [Indexed: 11/15/2023] Open
Abstract
BACKGROUND Boron-containing compounds, such as 4-borono-phenylalanine (BPA) are used as drugs for cancer treatment in the framework of Boron Neutron Capture Therapy (BNCT). Neutron irradiation of boron-rich compounds delivered to cancer cells triggers nuclear reactions that destroy cancer cells. PURPOSE We provide a modeling of the thermal neutron cross section of BPA, a drug used in Boron Neutron Capture Therapy (BNCT), to quantify the competing contributions of boron absorption against hydrogen scattering, for optimizing BNCT by minimizing the latter. METHODS We perform the experimental determination of the total neutron scattering cross section of BPA at thermal and epithermal neutron energies using neutron transmission measurements. We isolate the contribution related to the incoherent scattering by hydrogen atoms as a function of the neutron energy by means of the Average Functional Group Approximation, and we calculate the probability for a neutron of being absorbed as a function of the neutron energy both for BPA and for its variants where either one or all four aromatic hydrogen atoms are substituted by 19 F, and both for the samples with natural occurrence or enriched concentration of 10 B. RESULTS While referring to the already available literature for in vivo use of fluorinated BPA, we show that fluorine-rich variants of BPA increase the probability of neutrons being captured by the molecule. As the higher absorption efficiency of fluorinated BPA does not depend on whether the molecule is used in vivo or not, our results are promising for the higher efficiency of the boron neutron capture treatment. CONCLUSIONS Our results suggest a new advantage using fluorinated compounds for BNCT, in their optimized interaction with neutrons, in addition to their already known capability to be used for monitoring and pharmacokinetics studies using 19 F-Nuclear Magnetic Resonance or in 18 F-Positron Emission Tomography.
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Affiliation(s)
- Giovanni Romanelli
- Dipartimento di Fisica and NAST Centre, Università degli Studi di Roma "Tor Vergata", Rome, Italy
| | - Silvia Capuani
- National Research Council, Institute for Complex Systems (ISC), Rome, Italy
| | - Dalila Onorati
- Dipartimento di Fisica and NAST Centre, Università degli Studi di Roma "Tor Vergata", Rome, Italy
| | - Pierfrancesco Ulpiani
- Dipartimento di Scienze e Tecnologie Chimiche, Università degli Studi di Roma "Tor Vergata", Rome, Italy
| | - Enrico Preziosi
- Dipartimento di Fisica and NAST Centre, Università degli Studi di Roma "Tor Vergata", Rome, Italy
| | - Carla Andreani
- Dipartimento di Fisica and NAST Centre, Università degli Studi di Roma "Tor Vergata", Rome, Italy
- National Research Council, Institute of Polymers, Composites and Biomaterials (IPCB), Naples, Italy
| | - Roberto Senesi
- Dipartimento di Fisica and NAST Centre, Università degli Studi di Roma "Tor Vergata", Rome, Italy
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Noguere G, Xu S. Using effective temperature as a measure of the thermal scattering law uncertainties to UOX fuel calculations from room temperature to 80°C. EPJ NUCLEAR SCIENCES & TECHNOLOGIES 2022. [DOI: 10.1051/epjn/2022034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
The effective temperature Teff is an important physical quantity in neutronic calculations. It can be introduced in a Free Gas Model to approximate crystal lattice effects in the Doppler broadening of the neutron cross sections. In the last decade, a few research works proposed analytical or Monte-Carlo perturbation schemes for estimating uncertainties in neutronic calculations due to thermal scattering laws. However, the relationship between the reported results with Teff was not discussed. The present work aims to show how the effective temperature can measure the impact of the thermal scattering law uncertainties on neutronic calculations. The discussions are illustrated with Monte-Carlo calculations performed with the TRIPOLI-4® code on the MISTRAL-1 benchmark carried out in the EOLE facility of CEA Cadarache (France) from room temperature to 354 K (80°C). The uncertainty analysis is focused on the impact of the thermal scattering laws of H2O and UO2 on the neutron multiplication factor keff for UOX fuel moderated by water. When using the H2O and UO2 candidate files for the JEFF-4 library, the variation range of Teff leads to a keff uncertainty of 2.3 pcm/K, on average. In the temperature range investigated in this work, Teff uncertainties of ±20 K for H2O and ±10 K for UO2 give uncertainties on the multiplication factor that remains close to ±50 pcm. Such a low uncertainty confirms the improved accuracy achieved on the modelisation of the latest thermal scattering laws of interest for light water reactors. In the future evaluated nuclear data libraries, uncertainty budget analysis associated with the low neutron energy scattering process will be a marginal contribution compared to the capture process.
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Marquez Damian JI, DiJulio DD, Muhrer G. Nuclear data development at the European Spallation Source. JOURNAL OF NEUTRON RESEARCH 2021. [DOI: 10.3233/jnr-210014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Transport calculations for neutronic design require accurate nuclear data and validated computational tools. In the Spallation Physics Group, at the European Spallation Source, we perform shielding and neutron beam calculations to help the deployment of the instrument suite for the current high brilliance (top) moderator, as well for the design of the high intensity bottom moderator, currently under study for the facility. This work includes providing the best available nuclear data in addition to improving models and tools when necessary. In this paper we present the status of these activities, which include a set of thermal scattering kernels for moderator, reflector, and structural materials, the development of new kernels for beryllium considering crystallite size effects, nanodiamonds, liquid hydrogen and deuterium based on path integral molecular dynamics, and the use of the software package NCrystal to assist the development of nuclear data in the framework of the new HighNESS project.
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Affiliation(s)
| | | | - Günter Muhrer
- Spallation Physics Group, European Spallation Source ERIC, Lund, Sweden
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Glass Transition in Rice Pasta as Observed by Combined Neutron Scattering and Time-Domain NMR. Polymers (Basel) 2021; 13:polym13152426. [PMID: 34372027 PMCID: PMC8347043 DOI: 10.3390/polym13152426] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Revised: 07/16/2021] [Accepted: 07/20/2021] [Indexed: 12/18/2022] Open
Abstract
Experimental protocols aiming at the characterisation of glass transition often suffer from ambiguity. The ambition of the present study is to describe the glass transition in a complex, micro heterogeneous system, the dry rice pasta, in a most unambiguous manner, minimising the influence of technique-specific bias. To this end, we apply an unprecedented combination of experimental techniques. Apart from the usually used NMR and DSC, we employ, in a concurrent manner, neutron transmission, diffraction, and Compton scattering. This enables us to investigate the glass transition over a range of spatio-temporal scales that stretches over seven orders of magnitude. The results obtained by neutron diffraction and DSC reveal that dry rice pasta is almost entirely amorphous. Moreover, the glass transition is evidenced by neutron transmission and diffraction data and manifested as a significant decrease of the average sample number density in the temperature range between 40 and 60 °C. At the microscopic level, our NMR, neutron transmission and Compton scattering results provide evidence of changes in the secondary structure of the starch within the dry rice pasta accompanying the glass transition, whereby the long-range order provided by the polymer structure within the starch present in the dry rice pasta is partially lost.
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Romanelli G, Onorati D, Ulpiani P, Cancelli S, Perelli-Cippo E, Márquez Damián JI, Capelli SC, Croci G, Muraro A, Tardocchi M, Gorini G, Andreani C, Senesi R. Thermal neutron cross sections of amino acids from average contributions of functional groups. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2021; 33:285901. [PMID: 33906173 DOI: 10.1088/1361-648x/abfc13] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Accepted: 04/27/2021] [Indexed: 06/12/2023]
Abstract
The experimental thermal neutron cross sections of the 20 proteinogenic amino acids have been measured over the incident-neutron energy range spanning from 1 meV to 10 keV and data have been interpreted using the multi-phonon expansion based on first-principles calculations. The scattering cross section, dominated by the incoherent inelastic contribution from the hydrogen atoms, can be rationalised in terms of the average contributions of different functional groups, thus neglecting their correlation. These results can be used for modelling the total neutron cross sections of complex organic systems like proteins, muscles, or human tissues from a limited number of starting input functions. This simplification is of crucial importance for fine-tuning of transport simulations used in medical applications, including boron neutron capture therapy as well as secondary neutrons-emission induced during proton therapy. Moreover, the parametrized neutron cross sections allow a better treatment of neutron scattering experiments, providing detailed sample self-attenuation corrections for a variety of biological and soft-matter systems.
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Affiliation(s)
- Giovanni Romanelli
- ISIS Neutron and Muon Source, UKRI-STFC, Rutherford Appleton Laboratory, Harwell Campus, Didcot, Oxfordshire OX11 0QX, United Kingdom
| | - Dalila Onorati
- Università degli Studi di Roma 'Tor Vergata', Dipartimento di Fisica and NAST Centre, Via della Ricerca Scientifica 1, Roma 00133, Italy
| | - Pierfrancesco Ulpiani
- Università degli Studi di Roma 'Tor Vergata', Dipartimento di Scienze e Tecnologie Chimiche, Via della Ricerca Scientifica 1, Roma 00133, Italy
| | | | | | | | - Silvia C Capelli
- ISIS Neutron and Muon Source, UKRI-STFC, Rutherford Appleton Laboratory, Harwell Campus, Didcot, Oxfordshire OX11 0QX, United Kingdom
| | - Gabriele Croci
- Università di Milano-Bicocca, Piazza della Scienza 3, Milano, Italy
- Istituto per la Scienza e Tecnologia dei Plasmi, CNR, via Cozzi 53, 20125 Milano, Italy
| | - Andrea Muraro
- Istituto per la Scienza e Tecnologia dei Plasmi, CNR, via Cozzi 53, 20125 Milano, Italy
| | - Marco Tardocchi
- Istituto per la Scienza e Tecnologia dei Plasmi, CNR, via Cozzi 53, 20125 Milano, Italy
| | - Giuseppe Gorini
- Università di Milano-Bicocca, Piazza della Scienza 3, Milano, Italy
| | - Carla Andreani
- Università degli Studi di Roma 'Tor Vergata', Dipartimento di Fisica and NAST Centre, Via della Ricerca Scientifica 1, Roma 00133, Italy
- CNR-ISM, Area della Ricerca di Roma Tor Vergata, Via del Fosso del Cavaliere 100, 00133 Roma, Italy
| | - Roberto Senesi
- Università degli Studi di Roma 'Tor Vergata', Dipartimento di Fisica and NAST Centre, Via della Ricerca Scientifica 1, Roma 00133, Italy
- CNR-IPCF, Sezione di Messina, Viale Ferdinando Stagno d'Alcontres 37, Messina, 98158, Italy
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