Quantum Beam Science最新文献_第8页

Modifications of Metallic and Inorganic Materials by Using Ion/Electron Beams 离子/电子束对金属和无机材料的改性

IF 1.4

Quantum Beam Science Pub Date : 2021-12-29 DOI: 10.3390/qubs6010001

A. Iwase

引用次数: 0

High-Transmission Neutron Optical Devices Utilizing Micro-Machined Structures 利用微机械结构的高透射中子光学器件

IF 1.4

Quantum Beam Science Pub Date : 2021-12-25 DOI: 10.3390/qubs7010010

C. Kapahi, D. Sarenac, M. Bleuel, D. Cory, B. Heacock, M. Henderson, Michael G. Huber, I. Taminiau, D. Pushin

引用次数: 1

Laser Peening Analysis of Aluminum 5083: A Finite Element Study 5083铝激光喷丸分析的有限元研究

IF 1.4

Quantum Beam Science Pub Date : 2021-12-07 DOI: 10.3390/qubs5040034

A. Tajyar, Noah Holtham, N. Brooks, L. Hackel, Vincent R. Sherman, Alireza Beheshti, K. Davami

引用次数: 2

Measurement of Neutron Dose Equivalent within and Outside of a LINAC Treatment Vault Using a Neutron Survey Meter 使用中子测量仪测量LINAC处理库内外的中子剂量当量

IF 1.4

Quantum Beam Science Pub Date : 2021-11-30 DOI: 10.3390/qubs5040033

D. Tai, T. Loan, A. Sulieman, N. Tamam, H. Omer, D. Bradley

{"title":"Measurement of Neutron Dose Equivalent within and Outside of a LINAC Treatment Vault Using a Neutron Survey Meter","authors":"D. Tai, T. Loan, A. Sulieman, N. Tamam, H. Omer, D. Bradley","doi":"10.3390/qubs5040033","DOIUrl":"https://doi.org/10.3390/qubs5040033","url":null,"abstract":"This work concerns neutron doses associated with the use of a Siemens Primus M5497 electron accelerator, which is operated in the photon mode at 15 MV. The conditions offer a situation within which a fraction of the bremsstrahlung emission energies exceed the photoneutron threshold. For different field sizes, an investigation has been made of neutron dose equivalent values at various measurement locations, including: (i) At the treatment table, at a source-surface distance of 100 cm; (ii) at the level of the floor directly adjacent to the treatment table; and (iii) in the control room and patient waiting area. The evaluated neutron dose equivalent was found to range from 0.0001 to 8.6 mSv/h, notably with the greatest value at the level of the floor directly adjacent to the treatment couch (8.6 mSv/h) exceeding the greatest value on the treatment table (5.5 mSv/h). Low values ranging from unobservable to between 0.0001 to 0.0002 mSv/h neutron dose were recorded around the control room and patient waiting area. For measurements on the floor, the study showed the dose equivalent to be greatest with the jaws closed. These data, most particularly concerning neutron distribution within the treatment room, are of great importance in making steps towards improving patient safety via the provision of protective measures.","PeriodicalId":31879,"journal":{"name":"Quantum Beam Science","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2021-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41837953","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Nanopore Formation in CeO2 Single Crystal by Ion Irradiation: A Molecular Dynamics Study 离子辐照在CeO2单晶中形成纳米孔的分子动力学研究

IF 1.4

Quantum Beam Science Pub Date : 2021-11-18 DOI: 10.3390/qubs5040032

Y. Sasajima, R. Kaminaga, N. Ishikawa, A. Iwase

引用次数: 1

X-ray Imaging-Based Void Fraction Measurement in Saturated Flow Boiling Experiments with Seawater Coolant 海水冷却剂饱和流沸腾实验中基于x射线成像的空隙率测量

IF 1.4

Quantum Beam Science Pub Date : 2021-11-15 DOI: 10.3390/qubs5040031

S. Eckels, Zayed Ahmed, M. Ross, D. Franken, S. Eckels, H. Bindra

{"title":"X-ray Imaging-Based Void Fraction Measurement in Saturated Flow Boiling Experiments with Seawater Coolant","authors":"S. Eckels, Zayed Ahmed, M. Ross, D. Franken, S. Eckels, H. Bindra","doi":"10.3390/qubs5040031","DOIUrl":"https://doi.org/10.3390/qubs5040031","url":null,"abstract":"Recent studies have shown that the presence of dissolved salts in water can exhibit peculiar flow boiling and two-phase flow regimes. Two-phase flow and convective flow boiling are typically characterized with the help of void fraction measurements. To quantitatively improve our understanding of two-phase flow and boiling phenomenon with seawater coolant, void fraction data are needed, which can not be obtained from optical imaging. In this paper, we present experimental void fraction measurements of saturated flow boiling of tap water and seawater using X-ray radiography. X-rays with a maximum energy level of 40 KeV were used for imaging the exit region of the heated test section. At lower heat flux levels, the two phase flow in seawater was bubbly and homogeneous in nature, resulting in higher void fractions as compared to tap water. With an increase in heat flux, the flow regime was similar to slug flow, and void fraction measurements approached similarity with tap water. The predicted pressure drop using the measured void faction shows good agreement with the measured total pressure drop across the test section, demonstrating the validity of the measurement process.","PeriodicalId":31879,"journal":{"name":"Quantum Beam Science","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2021-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47440044","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Modification of SiO2, ZnO, Fe2O3 and TiN Films by Electronic Excitation under High Energy Ion Impact 高能离子冲击下SiO2、ZnO、Fe2O3和TiN薄膜的电子激发改性

IF 1.4

Quantum Beam Science Pub Date : 2021-10-27 DOI: 10.3390/qubs5040030

N. Matsunami, M. Sataka, S. Okayasu, B. Tsuchiya

{"title":"Modification of SiO2, ZnO, Fe2O3 and TiN Films by Electronic Excitation under High Energy Ion Impact","authors":"N. Matsunami, M. Sataka, S. Okayasu, B. Tsuchiya","doi":"10.3390/qubs5040030","DOIUrl":"https://doi.org/10.3390/qubs5040030","url":null,"abstract":"It has been known that the modification of non-metallic solid materials (oxides, nitrides, etc.), e.g., the formation of tracks, sputtering representing atomic displacement near the surface and lattice disordering are induced by electronic excitation under high-energy ion impact. We have investigated lattice disordering by the X-ray diffraction (XRD) of SiO2, ZnO, Fe2O3 and TiN films and have also measured the sputtering yields of TiN for a comparison of lattice disordering with sputtering. We find that both the degradation of the XRD intensity per unit ion fluence and the sputtering yields follow the power-law of the electronic stopping power and that these exponents are larger than unity. The exponents for the XRD degradation and sputtering are found to be comparable. These results imply that similar mechanisms are responsible for the lattice disordering and electronic sputtering. A mechanism of electron–lattice coupling, i.e., the energy transfer from the electronic system into the lattice, is discussed based on a crude estimation of atomic displacement due to Coulomb repulsion during the short neutralization time (~fs) in the ionized region. The bandgap scheme or exciton model is examined.","PeriodicalId":31879,"journal":{"name":"Quantum Beam Science","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2021-10-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44167182","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Recent Progress in the Development of a-Se/CMOS Sensors for X-ray Detection a-Se/CMOS X射线探测传感器的研究进展

IF 1.4

Quantum Beam Science Pub Date : 2021-10-18 DOI: 10.3390/qubs5040029

K. Hellier, Emmie Benard, C. Scott, K. Karim, S. Abbaszadeh

{"title":"Recent Progress in the Development of a-Se/CMOS Sensors for X-ray Detection","authors":"K. Hellier, Emmie Benard, C. Scott, K. Karim, S. Abbaszadeh","doi":"10.3390/qubs5040029","DOIUrl":"https://doi.org/10.3390/qubs5040029","url":null,"abstract":"Amorphous selenium (a-Se) is a glass-former capable of deposition at high rates by thermal evaporation over a large area. It was chosen as a direct conversion material due to its appealing properties for imaging in both low and high X-ray energy ranges (<30 keV and <30 keV, respectively). It has a bandgap of 2.2 eV and can achieve high photodetection efficiency at short wavelengths less than 400 nm which makes it appealing for indirect conversion detectors. The integration of a-Se with readout integrated circuits started with thin-film transistors for digital flat panel X-ray detectors. With increasing applications in life science, biomedical imaging, X-ray imaging, high energy physics, and industrial imaging that require high spatial resolution, the integration of a-Se and CMOS is one direct way to improve the high-contrast visualization and high-frequency response. Over the past decade, significant improvements in a-Se/CMOS technologies have been achieved with improvements to modulation transfer function and detective quantum efficiency. We summarize recent advances in integrating and photon-counting detectors based on a-Se coupled with CMOS readout and discuss some of the shortcomings in the detector structure, such as low charge conversion efficiency at low electric field and high dark current at high electric field. Different pixel architectures and their performance will be highlighted.","PeriodicalId":31879,"journal":{"name":"Quantum Beam Science","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2021-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49115854","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 6

Analysis of Cr(VI) Bioremediation by Citrobacter freundii Using Synchrotron Soft X-ray Scanning Transmission X-ray Microscopy 弗氏柠檬酸杆菌生物修复Cr（VI）的同步软X射线扫描透射X射线显微镜分析

IF 1.4

Quantum Beam Science Pub Date : 2021-09-28 DOI: 10.3390/qubs5040028

A. G. Anil, S. Swaraj, S. Subramanian, Praveen C Ramamurthy

{"title":"Analysis of Cr(VI) Bioremediation by Citrobacter freundii Using Synchrotron Soft X-ray Scanning Transmission X-ray Microscopy","authors":"A. G. Anil, S. Swaraj, S. Subramanian, Praveen C Ramamurthy","doi":"10.3390/qubs5040028","DOIUrl":"https://doi.org/10.3390/qubs5040028","url":null,"abstract":"Scanning transmission X-ray microscopy (STXM) was utilized for analysing the bioremediation of Cr(VI) by Citrobacter freundii, a species of gram-negative bacteria. The biosorption and bioreduction processes were analysed by the chemical mapping of cells biosorbed at different concentrations of Cr(VI). STXM spectromicroscopy images were recorded at O K-edge and Cr L-edge. A thorough analysis of the X-ray absorption features corresponding to different oxidation states of Cr in the biosorbed cell indicated the coexistence of Cr(III) and Cr(VI) at higher concentrations. This signifies the presence of partially reduced Cr(VI) in addition to biosorbed Cr(VI). In addition, the Cr(III) signal is intense compared with Cr(VI) at different regions of the cell indicating excess of reduced Cr. Speciation of adsorbed Cr was analysed for the spectral features of biosorbed cell and comparison with Cr standards. Analysis of absorption onset, L3/L2 ratio and absorption fine structure concludes that adsorbed Cr is predominantly present as Cr(III) hydroxide or oxyhydroxide. The evolution of absorption features in the duration of biosorption process was also studied. These time lapse studies depict the gradual decrement in Cr(VI) signal as biosorption proceeds. A strong evidence of interaction of Cr with the cell material was also observed. The obtained results provide insights into the biosorption process and chemical speciation of Cr on the cells.","PeriodicalId":31879,"journal":{"name":"Quantum Beam Science","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2021-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43286033","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Effect of Irradiation on Corrosion Behavior of 316L Steel in Lead-Bismuth Eutectic with Different Oxygen Concentrations 辐照对316L钢在不同氧浓度铅铋共晶中腐蚀行为的影响

IF 1.4

Quantum Beam Science Pub Date : 2021-08-31 DOI: 10.3390/qubs5030027

N. Okubo, Y. Fujimura, Masakatsu Tomobe

{"title":"Effect of Irradiation on Corrosion Behavior of 316L Steel in Lead-Bismuth Eutectic with Different Oxygen Concentrations","authors":"N. Okubo, Y. Fujimura, Masakatsu Tomobe","doi":"10.3390/qubs5030027","DOIUrl":"https://doi.org/10.3390/qubs5030027","url":null,"abstract":"In an accelerator-driven system (ADS), the beam window material of the spallation neutron target is heavily irradiated under severe conditions, in which the radiation damage and corrosion co-occur because of high-energy neutron and/or proton irradiation in the lead–bismuth flow. The materials used in ADSs must be compatible with the liquid metal (lead–bismuth eutectic (LBE)) to prevent issues such as liquid metal embrittlement (LME) and liquid metal corrosion (LMC). This study considers the LMC behavior after ion irradiation of 316L austenitic steel for self-ion irradiations followed by the corrosion tests in LBE with critical oxygen concentration. The 316L samples were irradiated by 10.5 MeV-Fe3+ ions at a temperature of 450 °C, up to 50 displacements per atom (dpa). After the corrosion test performed at 450 °C in LBE with low oxygen concentration, a surface of the nonirradiated area was not oxidized but appeared with locally corrosive morphology, Ni depletion, whereas an iron/chromium oxide layer fully covered the irradiated area. In the case of the corrosion surface with high oxygen concentration in LBE, the surface of the nonirradiated area was covered by an iron oxide layer only, whereas the irradiated area was covered by the duplex layers comprising iron and iron/chromium oxides. It is suggested that irradiation can enhance the oxide layer formation because of the enhancement of Fe and/or oxygen diffusion induced by the radiation defects in 316L steel.","PeriodicalId":31879,"journal":{"name":"Quantum Beam Science","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2021-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47614976","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4