Indirectly Cooled Radiation-Resistant Magnets for Hadron Target Station at J-PARC

2010 ◽  
Vol 20 (3) ◽  
pp. 344-347 ◽  
Author(s):  
H Takahashi ◽  
K Agari ◽  
E Hirose ◽  
M Ieiri ◽  
M Iio ◽  
...  
Keyword(s):  
Target Station ◽  
Radiation Resistant

scholarly journals Effects of Monovacancy and Divacancies on Hydrogen Solubility, Trapping and Diffusion Behaviors in fcc-Pd by First Principles

Materials ◽  
2020 ◽  
Vol 13 (21) ◽  
pp. 4876
Author(s):  
Bao-Long Ma ◽  
Yi-Yuan Wu ◽  
Yan-Hui Guo ◽  
Wen Yin ◽  
Qin Zhan ◽  
...  
Keyword(s):  
First Principles ◽  
Vacancy Defect ◽  
First Principles Calculations ◽  
Vacancy Defects ◽  
Target Station ◽  
Hydrogen Bubbles ◽  
Radiation Resistant ◽  
Key Issues ◽  
And Diffusion ◽  
Diffusion Behaviors

The hydrogen blistering phenomenon is one of the key issues for the target station of the accelerator-based neutron source. In the present study, the effect of monovacancies and divacancies defects on the solution, clustering and diffusion behaviors of H impurity in fcc-Pd were studied through first principles calculations. Our calculations prove that vacancies behave as an effective sink for H impurities. We found that, although the H-trap efficiency of the larger vacancy defect was reduced, its H-trap ability strengthened. There is a short-ranged area around the vacancy defects in which H impurities tend to diffuse to vacancy defects, gather and form hydrogen bubbles. Therefore, the characteristic of large vacancy defects formation in materials should be considered when screening anti-blistering materials for neutron-producing targets or when designing radiation resistant composite materials.

Alternative approaches to ultra-high resolution imaging

1991 ◽  
Vol 49 ◽  
pp. 650-651
Author(s):  
J.M. Cowley
Keyword(s):  
High Resolution ◽  
High Voltage ◽  
High Resolution Electron Microscopy ◽  
Crystal Defects ◽  
High Resolution Imaging ◽  
General Applicability ◽  
Resolution Electron ◽  
Radiation Resistant ◽  
Resolution Imaging ◽  
Alternative Approaches

By extrapolation of past experience, it would seem that the future of ultra-high resolution electron microscopy rests with the advances of electron optical engineering that are improving the instrumental stability of high voltage microscopes to achieve the theoretical resolutions of 1Å or better at 1MeV or higher energies. While these high voltage instruments will undoubtedly produce valuable results on chosen specimens, their general applicability has been questioned on the basis of the excessive radiation damage effects which may significantly modify the detailed structures of crystal defects within even the most radiation resistant materials in a period of a few seconds. Other considerations such as those of cost and convenience of use add to the inducement to consider seriously the possibilities for alternative approaches to the achievement of comparable resolutions.

Radiation-resistant magnetic field sensors based on SiO2(Ni)/Si structures

2019 ◽  
Vol 460 ◽  
pp. 209-211 ◽  
Author(s):  
E. Kaniukov ◽  
V. Bundyukova ◽  
D. Yakimchuk ◽  
A. Shumskaya ◽  
Yu. Bogatyrev ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Magnetic Field Sensors ◽  
Radiation Resistant

scholarly journals Coexistence of SOS-Dependent and SOS-Independent Regulation of DNA Repair Genes in Radiation-Resistant Deinococcus Bacteria

Cells ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 924
Author(s):  
Laurence Blanchard ◽  
Arjan de Groot
Keyword(s):  
Dna Repair ◽  
Deinococcus Radiodurans ◽  
Dna Repair Genes ◽  
Lesion Bypass ◽  
Radiation Resistant ◽  
Radiation Induced ◽  
Induced Mutagenesis ◽  
High Doses ◽  
Translesion Polymerases ◽  
Repair Genes

Deinococcus bacteria are extremely resistant to radiation and able to repair a shattered genome in an essentially error-free manner after exposure to high doses of radiation or prolonged desiccation. An efficient, SOS-independent response mechanism to induce various DNA repair genes such as recA is essential for radiation resistance. This pathway, called radiation/desiccation response, is controlled by metallopeptidase IrrE and repressor DdrO that are highly conserved in Deinococcus. Among various Deinococcus species, Deinococcus radiodurans has been studied most extensively. Its genome encodes classical DNA repair proteins for error-free repair but no error-prone translesion DNA polymerases, which may suggest that absence of mutagenic lesion bypass is crucial for error-free repair of massive DNA damage. However, many other radiation-resistant Deinococcus species do possess translesion polymerases, and radiation-induced mutagenesis has been demonstrated. At least dozens of Deinococcus species contain a mutagenesis cassette, and some even two cassettes, encoding error-prone translesion polymerase DnaE2 and two other proteins, ImuY and ImuB-C, that are probable accessory factors required for DnaE2 activity. Expression of this mutagenesis cassette is under control of the SOS regulators RecA and LexA. In this paper, we review both the RecA/LexA-controlled mutagenesis and the IrrE/DdrO-controlled radiation/desiccation response in Deinococcus.

scholarly journals Cancer-associated fibroblasts promote the survival of irradiated nasopharyngeal carcinoma cells via the NF-κB pathway

2021 ◽  
Vol 40 (1) ◽  
Author(s):  
Weiqiang Huang ◽  
Longshan Zhang ◽  
Mi Yang ◽  
Xixi Wu ◽  
Xiaoqing Wang ◽  
...  
Keyword(s):  
Dna Damage ◽  
Nasopharyngeal Carcinoma ◽  
Enrichment Analysis ◽  
Underlying Mechanism ◽  
Gene Set Enrichment Analysis ◽  
Cancer Associated Fibroblasts ◽  
Western Blot Assay ◽  
Damage Level ◽  
Radiation Resistant

Abstract Background Irradiation has emerged as a valid tool for nasopharyngeal carcinoma (NPC) in situ treatment; however, NPC derived from tissues treated with irradiation is a main cause cancer-related death. The purpose of this study is to uncover the underlying mechanism regarding tumor growth after irradiation and provided potential therapeutic strategy. Methods Fibroblasts were extracted from fresh NPC tissue and normal nasopharyngeal mucosa. Immunohistochemistry was conducted to measure the expression of α-SMA and FAP. Cytokines were detected by protein array chip and identified by real-time PCR. CCK-8 assay was used to detect cell proliferation. Radiation-resistant (IRR) 5-8F cell line was established and colony assay was performed to evaluate tumor cell growth after irradiation. Signaling pathways were acquired via gene set enrichment analysis (GSEA). Comet assay and γ-H2AX foci assay were used to measure DNA damage level. Protein expression was detected by western blot assay. In vivo experiment was performed subcutaneously. Results We found that radiation-resistant NPC tissues were constantly infiltrated with a greater number of cancer-associated fibroblasts (CAFs) compared to radiosensitive NPC tissues. Further research revealed that CAFs induced the formation of radioresistance and promoted NPC cell survival following irradiation via the IL-8/NF-κB pathway to reduce irradiation-induced DNA damage. Treatment with Tranilast, a CAF inhibitor, restricted the survival of CAF-induced NPC cells and attenuated the of radioresistance properties. Conclusions Together, these data demonstrate that CAFs can promote the survival of irradiated NPC cells via the NF-κB pathway and induce radioresistance that can be interrupted by Tranilast, suggesting the potential value of Tranilast in sensitizing NPC cells to irradiation.

scholarly journals Comparison of short-range order in irradiated dysprosium titanates

2021 ◽  
Vol 5 (1) ◽  
Author(s):  
Roman Sherrod ◽  
Eric C. O’Quinn ◽  
Igor M. Gussev ◽  
Cale Overstreet ◽  
Joerg Neuefeind ◽  
...  
Keyword(s):  
Long Range ◽  
Short Range ◽  
Structural Model ◽  
Ion Irradiation ◽  
Function Analysis ◽  
Ion Beam ◽  
Structural Response ◽  
Heavy Ion ◽  
Range Order ◽  
Radiation Resistant

AbstractThe structural response of Dy2TiO5 oxide under swift heavy ion irradiation (2.2 GeV Au ions) was studied over a range of structural length scales utilizing neutron total scattering experiments. Refinement of diffraction data confirms that the long-range orthorhombic structure is susceptible to ion beam-induced amorphization with limited crystalline fraction remaining after irradiation to 8 × 1012 ions/cm2. In contrast, the local atomic arrangement, examined through pair distribution function analysis, shows only subtle changes after irradiation and is still described best by the original orthorhombic structural model. A comparison to Dy2Ti2O7 pyrochlore oxide under the same irradiation conditions reveals a different behavior: while the dysprosium titanate pyrochlore is more radiation resistant over the long-range with smaller degree of amorphization as compared to Dy2TiO5, the former involves more local atomic rearrangements, best described by a pyrochlore-to-weberite-type transformation. These results highlight the importance of short-range and medium-range order analysis for a comprehensive description of radiation behavior.

scholarly journals Unravelling the secrets of the resistance of GaN to strongly ionising radiation

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Miguel C. Sequeira ◽  
Jean-Gabriel Mattei ◽  
Henrique Vazquez ◽  
Flyura Djurabekova ◽  
Kai Nordlund ◽  
...  
Keyword(s):  
Heavy Ions ◽  
Ionising Radiation ◽  
Atomistic Simulations ◽  
Extended Defects ◽  
Swift Heavy Ions ◽  
High Fluences ◽  
Radiation Resistant ◽  
Simulation And Experiment ◽  
Underlying Mechanisms ◽  
Radiation Hard

AbstractGaN is the most promising upgrade to the traditional Si-based radiation-hard technologies. However, the underlying mechanisms driving its resistance are unclear, especially for strongly ionising radiation. Here, we use swift heavy ions to show that a strong recrystallisation effect induced by the ions is the key mechanism behind the observed resistance. We use atomistic simulations to examine and predict the damage evolution. These show that the recrystallisation lowers the expected damage levels significantly and has strong implications when studying high fluences for which numerous overlaps occur. Moreover, the simulations reveal structures such as point and extended defects, density gradients and voids with excellent agreement between simulation and experiment. We expect that the developed modelling scheme will contribute to improving the design and test of future radiation-resistant GaN-based devices.

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