An outstanding challenge in materials science and physics is the harnessing of light for switching charge order in e.g., ferroelectrics. Here we propose a mechanism through which electrons in ferroelectric bilayers ex...
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High-entropy ceramics have been studied as potential candidates for applications in extreme environments, such as nuclear fusion reactors. Their beneficial properties and increased radiation tolerance are often attrib...
High-entropy ceramics have been studied as potential candidates for applications in extreme environments, such as nuclear fusion reactors. Their beneficial properties and increased radiation tolerance are often attributed to their compositional complexity achieved through equimolarity. A near-equimolar (CrNbTaTiW)C carbide, obtained by magnetron sputtering, was investigated using in situ TEM whilst being exposed to 300-keV Xe heavy ion irradiation at 573 K. The material did not show structural changes or amorphisation after irradiation to 8.5 dpa. The pristine material showed partial elemental segregation of Cr and Ti and after irradiation redistribution and homogenisation of the solid solution was observed. Furthermore, the coating showed signs of erosion damage near the surface and along some of the grain boundaries, likely due to sputtering during the energetic particle bombardment. This work suggests the response to irradiation in these novel multicomponent ceramics to be multifaceted—determined by an interplay of composition, microstructure, and constituent elements’ chemistry—going beyond simply equimolarity.
We try to resolve the longstanding controversy over the low-lying 1/2+ state in B9. Experimentally, the energies for this state show a gap between various measurements done by different groups and some of them reporte...
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We try to resolve the longstanding controversy over the low-lying 1/2+ state in B9. Experimentally, the energies for this state show a gap between various measurements done by different groups and some of them reported that the existence of the state is unclear. The situation is similar in the theoretical calculations. We study the existence and structure of the B9(1/2+) state based on our previous method for the α+α+N cluster model with the complex scaling method that well explains the measured photodisintegration cross section for the Be9(1/2+). We find two resonances at the energies of E1res=1.81 MeV with a decay width Γ=1.98 MeV and E2res=2.38 MeV, Γ=1.81 MeV in B9. The charge radii and the three-body channel configurations are calculated to see the properties of two resonances. We also calculate the level density of two resonances, which indicates the difficulty to distinguish them in the energy distribution.
This study aimed to assess the internal radiation exposure of patients who have undergone a Positron Emission Tomography (PET) scan using 18F-FDG radiopharmaceutical. A total of 24 patients (8 men, 16 women, with an a...
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The RPT method transforms the double heterogeneity problem into the traditional single heterogeneity problem, which has the advantages of simplicity and efficiency. However, the current RPT methods mainly focus on rod...
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The neutron-induced fission cross section of Pu239 was measured relative to U235(n,f) at the back-streaming white neutron beam line (Back-n) of the China Spallation Neutron Source (CSNS). A multicell fast fission ioni...
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The neutron-induced fission cross section of Pu239 was measured relative to U235(n,f) at the back-streaming white neutron beam line (Back-n) of the China Spallation Neutron Source (CSNS). A multicell fast fission ionization chamber was used to perform the measurement. The reliability of the measurement was verified by the high consistency of U235's resonances between the measurement and the evaluation data. The Pu239 fission cross sections from 4keV to 100MeV are obtained with 1.7–5.8 % uncertainty when unfolding uncertainties are excluded. The total uncertainties including the unfolding errors, which reflect the effect of the double-bunch unfolding method, are 2.6–15 % from 10keV to 100MeV.
Elastic scattering and breakup B8+p and Be7+2p angular distributions for C9+Pb208 at an incident energy of 303 MeV, around five times the Coulomb barrier, are reported. The data have been analyzed using the optical mo...
Elastic scattering and breakup B8+p and Be7+2p angular distributions for C9+Pb208 at an incident energy of 303 MeV, around five times the Coulomb barrier, are reported. The data have been analyzed using the optical model and the three-body continuum discretized coupled channels formalism, assuming B8+p and Be7+2p configurations. The elastic scattering angular distributions, both measured and calculated, exhibit a relatively minor suppression of the Coulomb rainbow. Calculations combining the elastic and nonelastic breakup contributions reproduce the breakup angular distributions rather well, apart from a slight overestimation observed for Be7 fragments at forward angles. Analyses of the breakup reactions reveal that the cross section for two-proton-removal from C9 is approximately twice as large as that for one-proton-removal, despite the close proximity of the one- and two-proton separation energies.
The cluster structures of (RhO)n- (n = 2-4) have been investigated using photoelectron (PE) velocity-map imaging in combined with density functional theory calculations. PE spectra provided the ADEs information of thr...
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Exposure to radiation from environmental, medical, and occupational sources is a serious health hazard, with genomic instability and oxidative stress being the major culprits. Honokiol (HKL), a biphenol derived from M...
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Exposure to radiation from environmental, medical, and occupational sources is a serious health hazard, with genomic instability and oxidative stress being the major culprits. Honokiol (HKL), a biphenol derived from Magnolia plants, has been shown to possess strong antioxidant activity. In this study, we investigated the radioprotective effect of HKL against ionizing radiation-induced damage, with its capacity to modulate the thioredoxin reductase/thioredoxin (TrxR/Trx) redox system being the focus of investigation. Specifically, human bronchial epithelial cells (BEAS-2B) and female C57BL/6 mice were exposed to 4 Gy X-ray or 2 Gy carbon ions for all experiments except mouse survival analysis, where 8.0 Gy X-ray or 5.0 Gy carbon ions were used. HKL was administered at 5.00 μM for cell experiments and 15.00 mg/kg for animal experiments. A comprehensive research framework utilizing in vitro cellular models and in vivo models, we demonstrated that HKL pretreatment greatly increased cell viability, inhibited DNA damage, and relieved reactive oxygen species (ROS) accumulation in irradiated cells. Molecular docking of TrxR with its specific selenocysteine (Sec498) active site and biochemical analyses identified that HKL stabilizes the TrxR/Trx redox system without direct inhibition of TrxR catalytic activity. HKL pretreatment also reduced the bystander effect and enhanced survival in irradiated mice, with significant protective effects observed specifically in lung tissues. suggesting its value as a radioprotective agent. This study elucidates the molecular mechanism through which HKL confers radiation protection by targeting the TrxR/Trx system for the first time. These findings highlight the radioprotective potential of HKL via TrxR/Trx system modulation, and provide a rationale for further preclinical evaluation.
Migration velocity of Ground Penetrating Radar (GPR) data is a low wavenumber attribute crucial for migration. Obtaining a migration velocity model, which is considered closer to a Root Mean Square (RMS) model, from z...
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ISBN:
(数字)9798350365597
ISBN:
(纸本)9798350365603
Migration velocity of Ground Penetrating Radar (GPR) data is a low wavenumber attribute crucial for migration. Obtaining a migration velocity model, which is considered closer to a Root Mean Square (RMS) model, from zero-offset (ZO) data requires analysis of the available diffractions whose density and (x, t) coverage is random. Thus, accuracy and efficiency of such a velocity model either for migration or its usage for interval velocity model estimation is not guaranteed. Here, with the aid of an Artificiaal Intelligence (AI) algorithm, which detects diffractions and usage of their kinematic information, we generate a diffraction velocity model used for the assignment of 2D weights for weighted multipath summation. The scope is to efficiently focus the scattered energy within a GPR section. We describe this methodology and demonstrate its application in enhancing the lateral continuity of reflections. We compare it with the multipath summation using lD weights with simulated data and present its application on marble assessment GPR data for imaging cracks in the subsurface structure.
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