Pub Date : 2024-12-10DOI: 10.1016/j.radphyschem.2024.112463
Yana L. Shabelnikova, Elena I. Suvorova
TEM, electron diffraction, energy dispersive X-ray spectrometry and electron energy loss spectroscopy characterization of a multilayer composite Ag/YBa2Cu3O6+δ/LaMnO3/MgO/Y2O3/Al2O3/Hastelloy after exposure to Xe and Kr ions with energies from E ≅ 0.04 to E ≅ 0.8 MeV/nucleon was carried out. Changes in the chemical composition, morphology and sizes of linear radiation defects, tracks, in the YBa2Cu3O6+δ and secondary phase precipitates were investigated. It was found that all radiation defects had amorphous structure regardless the ion energy, while the change in chemical composition was dependent on atomic radius (or mass) of stopping ion and atoms in samples. The diameters of linear defects remain constant for each material in the ion energy range used and distance passed by ions in the samples, about 1 μm, and correlate with the material parameters. The largest track diameters of 10–12 nm were registered in the YCuO2 phase, which has the lowest density, low melting point and the lowest threshold of electronic stopping power of track formation among all the studied compounds. The experimentally measured track diameters in YBCO and secondary phase precipitates were compared with the predictions of the analytical thermal spike model. It is shown that for dielectrics such as simple yttrium oxide and yttrium-copper oxide, with the stopping power of ions exceeding 10 keV/nm, the measured diameters agree with the calculated values within the experimental error or the deviation does not exceed 10%. The discrepancy between the sizes of the observed and calculated tracks at lower stopping powers, as well as the contradiction in the qualitative behavior of the track radius depending on the energy losses, may be due to the inaccuracy of the thermal spike model associated with the underlying significant assumptions.
{"title":"Analysis of chemical composition and morphology of linear radiation defects created by Kr and Xe ions with energies of 0.04–0.8 MeV/nucleon in YBa2Cu3O6+δ and in secondary phase precipitates: experiment and application of the analytical thermal spike model","authors":"Yana L. Shabelnikova, Elena I. Suvorova","doi":"10.1016/j.radphyschem.2024.112463","DOIUrl":"https://doi.org/10.1016/j.radphyschem.2024.112463","url":null,"abstract":"TEM, electron diffraction, energy dispersive X-ray spectrometry and electron energy loss spectroscopy characterization of a multilayer composite Ag/YBa<ce:inf loc=\"post\">2</ce:inf>Cu<ce:inf loc=\"post\">3</ce:inf>O<ce:inf loc=\"post\">6+δ</ce:inf>/LaMnO<ce:inf loc=\"post\">3</ce:inf>/MgO/Y<ce:inf loc=\"post\">2</ce:inf>O<ce:inf loc=\"post\">3</ce:inf>/Al<ce:inf loc=\"post\">2</ce:inf>O<ce:inf loc=\"post\">3</ce:inf>/Hastelloy after exposure to Xe and Kr ions with energies from E ≅ 0.04 to E ≅ 0.8 MeV/nucleon was carried out. Changes in the chemical composition, morphology and sizes of linear radiation defects, tracks, in the YBa<ce:inf loc=\"post\">2</ce:inf>Cu<ce:inf loc=\"post\">3</ce:inf>O<ce:inf loc=\"post\">6+δ</ce:inf> and secondary phase precipitates were investigated. It was found that all radiation defects had amorphous structure regardless the ion energy, while the change in chemical composition was dependent on atomic radius (or mass) of stopping ion and atoms in samples. The diameters of linear defects remain constant for each material in the ion energy range used and distance passed by ions in the samples, about 1 μm, and correlate with the material parameters. The largest track diameters of 10–12 nm were registered in the YCuO<ce:inf loc=\"post\">2</ce:inf> phase, which has the lowest density, low melting point and the lowest threshold of electronic stopping power of track formation among all the studied compounds. The experimentally measured track diameters in YBCO and secondary phase precipitates were compared with the predictions of the analytical thermal spike model. It is shown that for dielectrics such as simple yttrium oxide and yttrium-copper oxide, with the stopping power of ions exceeding 10 keV/nm, the measured diameters agree with the calculated values within the experimental error or the deviation does not exceed 10%. The discrepancy between the sizes of the observed and calculated tracks at lower stopping powers, as well as the contradiction in the qualitative behavior of the track radius depending on the energy losses, may be due to the inaccuracy of the thermal spike model associated with the underlying significant assumptions.","PeriodicalId":20861,"journal":{"name":"Radiation Physics and Chemistry","volume":"119 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142823119","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-10DOI: 10.1016/j.radphyschem.2024.112448
Jay W. Archer, Matthew J. Large, David Bolst, Dousatsu Sakata, Hoang Ngoc Tran, Konstantinos P. Chatzipapas, Vladimir Ivantchenko, Anatoly B. Rosenfeld, Sebastien Incerti, Jeremy M.C. Brown, Susanna Guatelli
The early DNA damage on the surface of the Moon due to GCR protons and alpha particles were assessed using a multiscale approach in Geant4. This consisted of three simulation stages. A periodic boundary conditions approach was used to obtain the radiation field on the surface and inside a proposed lunar habitat. The radiation field on the cellular scale was obtained in the organs of male and female astronauts using the ICRP145 tetrahedral mesh phantoms. This was subsequently simulated using a full human cell model in Geant4-DNA to obtain the early DNA damage. Geant4-DNA track structure ionisation models upper energy limits were extended to be able to model the interactions of the GCR at sub-cellular level, covering an energy range from a few eV up to 1TeV. Hadronic interactions and the modelling of induced radiochemical species were also implemented. The early DNA damage was assessed using the Geant4-DNA molecularDNA example. A greater yield of DNA damage was observed on the lunar surface compared with the habitat, and indirect damage due to induced hydroxyl radicals constituted most of the damage. This study demonstrates a complete simulation pipeline for the assessment of early DNA damage in astronauts in the space radiation environment.
{"title":"A multiscale nanodosimetric study of GCR protons and alpha particles in the organs of astronauts on the lunar surface","authors":"Jay W. Archer, Matthew J. Large, David Bolst, Dousatsu Sakata, Hoang Ngoc Tran, Konstantinos P. Chatzipapas, Vladimir Ivantchenko, Anatoly B. Rosenfeld, Sebastien Incerti, Jeremy M.C. Brown, Susanna Guatelli","doi":"10.1016/j.radphyschem.2024.112448","DOIUrl":"https://doi.org/10.1016/j.radphyschem.2024.112448","url":null,"abstract":"The early DNA damage on the surface of the Moon due to GCR protons and alpha particles were assessed using a multiscale approach in Geant4. This consisted of three simulation stages. A periodic boundary conditions approach was used to obtain the radiation field on the surface and inside a proposed lunar habitat. The radiation field on the cellular scale was obtained in the organs of male and female astronauts using the ICRP145 tetrahedral mesh phantoms. This was subsequently simulated using a full human cell model in Geant4-DNA to obtain the early DNA damage. Geant4-DNA track structure ionisation models upper energy limits were extended to be able to model the interactions of the GCR at sub-cellular level, covering an energy range from a few eV up to 1<ce:hsp sp=\"0.16667\"></ce:hsp>TeV. Hadronic interactions and the modelling of induced radiochemical species were also implemented. The early DNA damage was assessed using the Geant4-DNA <ce:italic>molecularDNA</ce:italic> example. A greater yield of DNA damage was observed on the lunar surface compared with the habitat, and indirect damage due to induced hydroxyl radicals constituted most of the damage. This study demonstrates a complete simulation pipeline for the assessment of early DNA damage in astronauts in the space radiation environment.","PeriodicalId":20861,"journal":{"name":"Radiation Physics and Chemistry","volume":"5 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142867719","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-06DOI: 10.1016/j.radphyschem.2024.112465
Zahra Al Timimi
Radiation-induced caries is the most frequent adverse reaction for patients undergoing radiation treatment for neck and head malignancies. An understanding of how radiation exposure alters tooth structure can lead to the advancement of robust and efficient restorative dentistry approaches. In this work, chemical compositions along with microstructural characteristics of radiation-induced caries-affected dentin have been contrasted to those of both radiation-irradiated and healthy dentin. The specimens of radiation-affected carious dentin and surrounding irradiated dentin were obtained from patients undergoing radiation treatment. The control group in this work included healthy dentin that had not been exposed to radiation. Numerous techniques, including energy-dispersive spectroscopy, Fourier transform infrared spectra, X-ray diffraction, and scanning electron microscopy; have been used to study the specimens. Different levels of microstructural degradation were seen in groups of carious and irradiated dentin, according to scanning electron microscopy. An investigation using energy-dispersive spectroscopy revealed that the carious in addition to irradiated dentin groups had higher quantities of Carbon (with P < 0.05). By contrast, the control group's Calcium and Phosphorus levels were significantly higher (with P < 0.05). In X-ray diffraction analysis, irradiated dentin along with carious dentin samples lacked the (1-1-2) and (3-0-0) peaks, and in Fourier transforms infrared spectroscopy, the carbonate peaks were less prominent. Radiation exposure may decrease hydroxyapatite concentrations, resulting in variable degrees of demineralization as well as degeneration since both irradiated and carious dentin show morphological and chemical changes.
{"title":"Radiation's effect on dental structures and caries induction in patients with head and neck cancer: Consequences for restorative therapy","authors":"Zahra Al Timimi","doi":"10.1016/j.radphyschem.2024.112465","DOIUrl":"https://doi.org/10.1016/j.radphyschem.2024.112465","url":null,"abstract":"Radiation-induced caries is the most frequent adverse reaction for patients undergoing radiation treatment for neck and head malignancies. An understanding of how radiation exposure alters tooth structure can lead to the advancement of robust and efficient restorative dentistry approaches. In this work, chemical compositions along with microstructural characteristics of radiation-induced caries-affected dentin have been contrasted to those of both radiation-irradiated and healthy dentin. The specimens of radiation-affected carious dentin and surrounding irradiated dentin were obtained from patients undergoing radiation treatment. The control group in this work included healthy dentin that had not been exposed to radiation. Numerous techniques, including energy-dispersive spectroscopy, Fourier transform infrared spectra, X-ray diffraction, and scanning electron microscopy; have been used to study the specimens. Different levels of microstructural degradation were seen in groups of carious and irradiated dentin, according to scanning electron microscopy. An investigation using energy-dispersive spectroscopy revealed that the carious in addition to irradiated dentin groups had higher quantities of Carbon (with P < 0.05). By contrast, the control group's Calcium and Phosphorus levels were significantly higher (with P < 0.05). In X-ray diffraction analysis, irradiated dentin along with carious dentin samples lacked the (1-1-2) and (3-0-0) peaks, and in Fourier transforms infrared spectroscopy, the carbonate peaks were less prominent. Radiation exposure may decrease hydroxyapatite concentrations, resulting in variable degrees of demineralization as well as degeneration since both irradiated and carious dentin show morphological and chemical changes.","PeriodicalId":20861,"journal":{"name":"Radiation Physics and Chemistry","volume":"92 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142823108","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A key challenge in multi-energy X-ray inspection systems is the effect of object positioning on material discrimination accuracy. This study addresses the issue by conducting experiments with various materials placed at different positions. Four wedge-shaped samples were tested at different heights and angles within a standard dual-energy cargo inspection system. The results demonstrated that object positioning significantly influences the distribution of radiation reaching the detectors, mainly due to variations in the amount of Compton-scattered X-rays. These changes notably affect material discrimination curves. Additionally, placing objects farther from the accelerator enhanced material discrimination accuracy by 4-14% and improved detection precision by 4%–14% for some detectors. The findings highlight the need for precise control over experimental conditions to achieve optimal material discrimination results. The insights gained from this study can contribute to optimizing multi-energy X-ray inspection systems, improving material discrimination capabilities, and enhancing precision in threat detection.
多能量 X 射线检测系统面临的一个主要挑战是物体定位对材料辨别精度的影响。本研究通过对放置在不同位置的各种材料进行实验来解决这一问题。在标准双能量货物检测系统中，以不同高度和角度对四个楔形样品进行了测试。结果表明，物体的位置会显著影响到达探测器的辐射分布，这主要是由于康普顿散射 X 射线量的变化造成的。这些变化会明显影响材料分辨曲线。此外，将物体放置在离加速器更远的地方，可将某些探测器的材料辨别精度提高 4%-14%，并将检测精度提高 4%-14%。研究结果强调了精确控制实验条件以获得最佳材料辨别结果的必要性。从这项研究中获得的启示有助于优化多能 X 射线检测系统、提高材料辨别能力和威胁检测精度。
{"title":"Impact of object positioning and Compton scattering on material discrimination in high-energy X-ray cargo scans","authors":"Hossein Barati, Seyed AmirHossein Feghhi, Rouhollah Azimirad","doi":"10.1016/j.radphyschem.2024.112444","DOIUrl":"https://doi.org/10.1016/j.radphyschem.2024.112444","url":null,"abstract":"A key challenge in multi-energy X-ray inspection systems is the effect of object positioning on material discrimination accuracy. This study addresses the issue by conducting experiments with various materials placed at different positions. Four wedge-shaped samples were tested at different heights and angles within a standard dual-energy cargo inspection system. The results demonstrated that object positioning significantly influences the distribution of radiation reaching the detectors, mainly due to variations in the amount of Compton-scattered X-rays. These changes notably affect material discrimination curves. Additionally, placing objects farther from the accelerator enhanced material discrimination accuracy by 4-14% and improved detection precision by 4%–14% for some detectors. The findings highlight the need for precise control over experimental conditions to achieve optimal material discrimination results. The insights gained from this study can contribute to optimizing multi-energy X-ray inspection systems, improving material discrimination capabilities, and enhancing precision in threat detection.","PeriodicalId":20861,"journal":{"name":"Radiation Physics and Chemistry","volume":"88 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142867720","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-04DOI: 10.1016/j.radphyschem.2024.112450
Weizhe Huang, Yuting Zhang, Taj Wali Khan, Nuo Chen, Chunkai Xu, Enliang Wang, Xu Shan, Xiangjun Chen
Absolute cross sections for electron impact ionization and dissociation of the planetary atmospherically important molecule, methane, have been measured in a wide energy range from 350 to 8000 eV using an ion momentum imaging spectrometer. The partial ionization cross sections (PICSs) of ionic fragments CH4+, CH3+, CH2+, CH+, C+, H+ and H2+, as well as five dissociation channels are obtained. The total ionization cross sections are also deduced by summing up the PICSs for all the observed ions. The PICSs of the ionic fragments at electron impact energies above 2000 eV and the PICSs of the dissociation processes are reported for the first time. The comparison and evaluation of the previous measurements reveals that the data of Lindsay and Mangan (2003) are in global agreement with present results, recommending reliable cross sections for electron impact ionization of methane from threshold to 8000 eV.
{"title":"Absolute cross sections for electron impact ionization and dissociation of methane from 350 to 8000 eV","authors":"Weizhe Huang, Yuting Zhang, Taj Wali Khan, Nuo Chen, Chunkai Xu, Enliang Wang, Xu Shan, Xiangjun Chen","doi":"10.1016/j.radphyschem.2024.112450","DOIUrl":"https://doi.org/10.1016/j.radphyschem.2024.112450","url":null,"abstract":"Absolute cross sections for electron impact ionization and dissociation of the planetary atmospherically important molecule, methane, have been measured in a wide energy range from 350 to 8000 eV using an ion momentum imaging spectrometer. The partial ionization cross sections (PICSs) of ionic fragments CH<ce:inf loc=\"post\">4</ce:inf><ce:sup loc=\"post\">+</ce:sup>, CH<ce:inf loc=\"post\">3</ce:inf><ce:sup loc=\"post\">+</ce:sup>, CH<ce:inf loc=\"post\">2</ce:inf><ce:sup loc=\"post\">+</ce:sup>, CH<ce:sup loc=\"post\">+</ce:sup>, C<ce:sup loc=\"post\">+</ce:sup>, H<ce:sup loc=\"post\">+</ce:sup> and H<ce:inf loc=\"post\">2</ce:inf><ce:sup loc=\"post\">+</ce:sup>, as well as five dissociation channels are obtained. The total ionization cross sections are also deduced by summing up the PICSs for all the observed ions. The PICSs of the ionic fragments at electron impact energies above 2000 eV and the PICSs of the dissociation processes are reported for the first time. The comparison and evaluation of the previous measurements reveals that the data of Lindsay and Mangan (2003) are in global agreement with present results, recommending reliable cross sections for electron impact ionization of methane from threshold to 8000 eV.","PeriodicalId":20861,"journal":{"name":"Radiation Physics and Chemistry","volume":"14 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142788813","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The present study proposes and demonstrates stable passive mode-locking in a laser operating at a wavelength of 2.0 μm by coupling a vanadium carbide MXene/polyvinyl alcohol (V2C/PVA) film, acting as a saturable absorber (SA), into the cavity of a Thulium/Holmium co-doped fiber laser (THDFL). The V2C/PVA film was successfully fabricated through a solution casting method. Initially, the V2C MXene was prepared using the molten salt method, wherein the aluminium (Al) layers were extracted from the V2AlC MAX phase precursor. The fabricated V2C/PVA film SA exhibits favourable nonlinear absorption properties, with recorded values of approximately 50% for modulation depth, 1 kW/cm2 for saturation intensity, and 50% for non-saturable loss. Achieving mode-locking at 1958.97 nm required a pump power of 283.5 mW, resulting in a 3-dB bandwidth of 4 nm. The SA generated stable pulses with an 18.69 MHz repetition rate, a pulse width of 1.6 ps, and a high signal-to-noise ratio (SNR) of around 60 dB. The research findings will pave the way for the application of V2C/PVA film SA in the field of ultrafast lasers.
{"title":"Passive technique of generating soliton mode-locked in thulium/holmium doped fiber laser employing MXene/Polyvinyl alcohol film","authors":"Hissah Saedoon Albaqawi, Fekhra Hedhili, Waed Alahmad","doi":"10.1016/j.radphyschem.2024.112461","DOIUrl":"https://doi.org/10.1016/j.radphyschem.2024.112461","url":null,"abstract":"The present study proposes and demonstrates stable passive mode-locking in a laser operating at a wavelength of 2.0 μm by coupling a vanadium carbide MXene/polyvinyl alcohol (V<ce:inf loc=\"post\">2</ce:inf>C/PVA) film, acting as a saturable absorber (SA), into the cavity of a Thulium/Holmium co-doped fiber laser (THDFL). The V<ce:inf loc=\"post\">2</ce:inf>C/PVA film was successfully fabricated through a solution casting method. Initially, the V<ce:inf loc=\"post\">2</ce:inf>C MXene was prepared using the molten salt method, wherein the aluminium (Al) layers were extracted from the V<ce:inf loc=\"post\">2</ce:inf>AlC MAX phase precursor. The fabricated V<ce:inf loc=\"post\">2</ce:inf>C/PVA film SA exhibits favourable nonlinear absorption properties, with recorded values of approximately 50% for modulation depth, 1 kW/cm<ce:sup loc=\"post\">2</ce:sup> for saturation intensity, and 50% for non-saturable loss. Achieving mode-locking at 1958.97 nm required a pump power of 283.5 mW, resulting in a 3-dB bandwidth of 4 nm. The SA generated stable pulses with an 18.69 MHz repetition rate, a pulse width of 1.6 ps, and a high signal-to-noise ratio (SNR) of around 60 dB. The research findings will pave the way for the application of V<ce:inf loc=\"post\">2</ce:inf>C/PVA film SA in the field of ultrafast lasers.","PeriodicalId":20861,"journal":{"name":"Radiation Physics and Chemistry","volume":"39 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142788829","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-04DOI: 10.1016/j.radphyschem.2024.112462
D.K. Swami, Sarvesh Kumar, S. Ojha, R.K. Karn
The charge state distribution of Si projectiles with energies ranging from 1.78 to 3.93 MeV/u, and initial charge states Sip+(p=4−10), was investigated after traversing a 10 μg/cm2 carbon foil. This study was focused on determining the relevant parameters of the outgoing projectile such as the charge state distribution fraction (Fq), the mean charge state (qm), distribution width (w), and asymmetric/skewness parameter (s). These parameters were then compared with predictions from the Fermi gas model and ETACHA4. Notably, a significant disparity was observed between the experimental measurements and the theoretical calculations, with the latter overestimating the former. This overestimation was attributed to non-radiative electron capture (NREC) occurring at the exit surface, influenced by the wake and dynamic screening effects. Understanding and accurately determining the charge state distribution parameters hold immense importance in various scientific applications including in the field of plasma studies, these fractions of charge states are directly utilized to tackle complex problems and facilitate the detection of superheavy ions. Furthermore, these parameters play a vital role in enhancing our understanding of ion behavior, collision dynamics, and plasma characteristics. The insight observed from such parameters may be used to refine the theoretical models for accurate predictions and in planning of experiments involving ion interactions.
{"title":"Charge state distribution for 1.78–3.93 MeV/u Si projectiles passing through 10 [formula omitted] carbon foil","authors":"D.K. Swami, Sarvesh Kumar, S. Ojha, R.K. Karn","doi":"10.1016/j.radphyschem.2024.112462","DOIUrl":"https://doi.org/10.1016/j.radphyschem.2024.112462","url":null,"abstract":"The charge state distribution of Si projectiles with energies ranging from 1.78 to 3.93 MeV/u, and initial charge states <mml:math altimg=\"si2.svg\"><mml:mrow><mml:msup><mml:mrow><mml:mi>S</mml:mi><mml:mi>i</mml:mi></mml:mrow><mml:mrow><mml:mi>p</mml:mi><mml:mo>+</mml:mo></mml:mrow></mml:msup><mml:mrow><mml:mo stretchy=\"true\">(</mml:mo><mml:mrow><mml:mi>p</mml:mi><mml:mo linebreak=\"badbreak\">=</mml:mo><mml:mn>4</mml:mn><mml:mo linebreak=\"badbreak\">−</mml:mo><mml:mn>10</mml:mn></mml:mrow><mml:mo stretchy=\"true\">)</mml:mo></mml:mrow></mml:mrow></mml:math>, was investigated after traversing a 10 <mml:math altimg=\"si1.svg\"><mml:mrow><mml:mi>μ</mml:mi><mml:mi>g</mml:mi><mml:mo linebreak=\"goodbreak\" linebreakstyle=\"after\">/</mml:mo><mml:msup><mml:mrow><mml:mi>c</mml:mi><mml:mi>m</mml:mi></mml:mrow><mml:mn>2</mml:mn></mml:msup></mml:mrow></mml:math> carbon foil. This study was focused on determining the relevant parameters of the outgoing projectile such as the charge state distribution fraction (<mml:math altimg=\"si3.svg\"><mml:mrow><mml:msub><mml:mi>F</mml:mi><mml:mi>q</mml:mi></mml:msub></mml:mrow></mml:math>), the mean charge state <mml:math altimg=\"si4.svg\"><mml:mrow><mml:mo stretchy=\"true\">(</mml:mo><mml:msub><mml:mi>q</mml:mi><mml:mi>m</mml:mi></mml:msub><mml:mo stretchy=\"true\">)</mml:mo></mml:mrow></mml:math>, distribution width (w), and asymmetric/skewness parameter (s). These parameters were then compared with predictions from the Fermi gas model and ETACHA4. Notably, a significant disparity was observed between the experimental measurements and the theoretical calculations, with the latter overestimating the former. This overestimation was attributed to non-radiative electron capture (NREC) occurring at the exit surface, influenced by the wake and dynamic screening effects. Understanding and accurately determining the charge state distribution parameters hold immense importance in various scientific applications including in the field of plasma studies, these fractions of charge states are directly utilized to tackle complex problems and facilitate the detection of superheavy ions. Furthermore, these parameters play a vital role in enhancing our understanding of ion behavior, collision dynamics, and plasma characteristics. The insight observed from such parameters may be used to refine the theoretical models for accurate predictions and in planning of experiments involving ion interactions.","PeriodicalId":20861,"journal":{"name":"Radiation Physics and Chemistry","volume":"4 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142790185","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Cellulosic materials make up a significant fraction of the current low- and intermediate-level radioactive waste. During storage and disposal, radiolytic degradation of such materials is inevitable and can occur under both oxic and anoxic conditions. In addition, the highly alkaline cementitious environment of a disposal system promotes the alkaline degradation of cellulosic materials, producing radionuclide-complexing agents, such as isosaccharinic acid (ISA). As radiolytic degradation changes the physicochemical properties of cellulose, it could also affect its alkaline degradation and thus the production of ISA during disposal. Hence, in the present work, we investigated the alkaline degradation of pre-irradiated cellulosic tissues, which are representative of real radioactive waste. Pre-irradiation occurred by exposing tissues to γ-irradiation under oxic or anoxic conditions at absorbed doses up to 1.4 MGy and at two different dose rates. These irradiated tissues were then submerged in artificially prepared cement water (initial pH of 13.3) and monitored over 2.5 years. The results show a significantly faster production and release of dissolved organic carbon and ISA with an increasing absorbed dose during pre-irradiation, and even more so when oxygen is present during irradiation. The irradiation dose rate did not affect the subsequent alkaline degradation rate. Taken together, this work demonstrates that irradiation of cellulosic materials in radioactive waste during storage and disposal will accelerate their alkaline degradation under disposal conditions. Consequently, radionuclide-complexing agents such as ISA will form at rates far exceeding those anticipated from alkaline degradation alone. These findings are therefore pivotal for improving long-term predictions of the ISA production in radioactive waste.
{"title":"Gamma irradiation accelerates alkaline degradation of cellulosic materials in radioactive waste","authors":"Bleyen Nele, Van Gompel Veerle, Durce Delphine, Nushi Enida, Valcke Elie","doi":"10.1016/j.radphyschem.2024.112464","DOIUrl":"https://doi.org/10.1016/j.radphyschem.2024.112464","url":null,"abstract":"Cellulosic materials make up a significant fraction of the current low- and intermediate-level radioactive waste. During storage and disposal, radiolytic degradation of such materials is inevitable and can occur under both oxic and anoxic conditions. In addition, the highly alkaline cementitious environment of a disposal system promotes the alkaline degradation of cellulosic materials, producing radionuclide-complexing agents, such as isosaccharinic acid (ISA). As radiolytic degradation changes the physicochemical properties of cellulose, it could also affect its alkaline degradation and thus the production of ISA during disposal. Hence, in the present work, we investigated the alkaline degradation of pre-irradiated cellulosic tissues, which are representative of real radioactive waste. Pre-irradiation occurred by exposing tissues to γ-irradiation under oxic or anoxic conditions at absorbed doses up to 1.4 MGy and at two different dose rates. These irradiated tissues were then submerged in artificially prepared cement water (initial pH of 13.3) and monitored over 2.5 years. The results show a significantly faster production and release of dissolved organic carbon and ISA with an increasing absorbed dose during pre-irradiation, and even more so when oxygen is present during irradiation. The irradiation dose rate did not affect the subsequent alkaline degradation rate. Taken together, this work demonstrates that irradiation of cellulosic materials in radioactive waste during storage and disposal will accelerate their alkaline degradation under disposal conditions. Consequently, radionuclide-complexing agents such as ISA will form at rates far exceeding those anticipated from alkaline degradation alone. These findings are therefore pivotal for improving long-term predictions of the ISA production in radioactive waste.","PeriodicalId":20861,"journal":{"name":"Radiation Physics and Chemistry","volume":"244 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142823111","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Energy-resolving photon-counting detectors (ERPCDs) are expected to enable novel functional diagnosis using quantitative X-ray images such as effective atomic number (Zeff) images. In this simulation study, we sought to optimize the settings related to tube voltage and energy windows.
{"title":"Optimization of energy windows to calculate quantitative X-ray images using an energy-resolving photon-counting detector: A simulation study","authors":"Rina Nishigami, Daiki Kobayashi, Natsumi Kimoto, Takashi Asahara, Tatsuya Maeda, Tomonobu Haba, Yuki Kanazawa, Shuichiro Yamamoto, Hiroaki Hayashi","doi":"10.1016/j.radphyschem.2024.112460","DOIUrl":"https://doi.org/10.1016/j.radphyschem.2024.112460","url":null,"abstract":"Energy-resolving photon-counting detectors (ERPCDs) are expected to enable novel functional diagnosis using quantitative X-ray images such as effective atomic number (Z<ce:inf loc=\"post\">eff</ce:inf>) images. In this simulation study, we sought to optimize the settings related to tube voltage and energy windows.","PeriodicalId":20861,"journal":{"name":"Radiation Physics and Chemistry","volume":"16 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142823112","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-04DOI: 10.1016/j.radphyschem.2024.112466
Juniastel Rajagukguk, Pintor Simamora, Ladestam Sitinjak, Elyzabeth Simanullang, C.S. Sarumaha, N. Intachai, S. Kothan, J. kaewkhao
Neodymium ions (Nd³⁺) doped into quartz sand and silicate oxide-based glass mediums have been synthesized using the melt-quenching method. The resulting glass samples adhere to the chemical compositions of 5 quartz sand (QS) + 50 B₂O₃ + 10 BaO + 30 Na₂O + 0.5Nd₂O₃ and 5SiO₂ + 50B₂O₃ + 10BaO + 30Na₂O + 0.5Nd₂O₃. These glasses were characterized by density, refractive index, X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and absorption spectrum. The quartz sand samples exhibited higher refractive index and molar volume compared to the silica borate samples. XRD spectra revealed the structural properties of the glass samples, while FTIR spectra were recorded across wavelengths from 650 to 4000 cm⁻1. The absorption spectra were observed in the UV–Vis–NIR range from 350 to 1000 nm, revealing 11 transition peaks. Additionally, three emission peaks were identified within the wavelength range of 800–1500 nm, along with the decay time of the glass samples.
{"title":"NIR luminescence properties of Nd3+ ion doped glasses medium based on Huta Ginjang quartz sand","authors":"Juniastel Rajagukguk, Pintor Simamora, Ladestam Sitinjak, Elyzabeth Simanullang, C.S. Sarumaha, N. Intachai, S. Kothan, J. kaewkhao","doi":"10.1016/j.radphyschem.2024.112466","DOIUrl":"https://doi.org/10.1016/j.radphyschem.2024.112466","url":null,"abstract":"Neodymium ions (Nd³⁺) doped into quartz sand and silicate oxide-based glass mediums have been synthesized using the melt-quenching method. The resulting glass samples adhere to the chemical compositions of 5 quartz sand (QS) + 50 B₂O₃ + 10 BaO + 30 Na₂O + 0.5Nd₂O₃ and 5SiO₂ + 50B₂O₃ + 10BaO + 30Na₂O + 0.5Nd₂O₃. These glasses were characterized by density, refractive index, X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and absorption spectrum. The quartz sand samples exhibited higher refractive index and molar volume compared to the silica borate samples. XRD spectra revealed the structural properties of the glass samples, while FTIR spectra were recorded across wavelengths from 650 to 4000 cm⁻<ce:sup loc=\"post\">1</ce:sup>. The absorption spectra were observed in the UV–Vis–NIR range from 350 to 1000 nm, revealing 11 transition peaks. Additionally, three emission peaks were identified within the wavelength range of 800–1500 nm, along with the decay time of the glass samples.","PeriodicalId":20861,"journal":{"name":"Radiation Physics and Chemistry","volume":"49 1","pages":""},"PeriodicalIF":2.9,"publicationDate":"2024-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142867718","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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