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k_(eff)uncertainty quantification and analysis due to nuclear data during the full lifetime burnup calculation for a small-sized prismatic high temperature gas-cooled reactor

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nuclear Science and Techniques 2021年第11期32卷 105-118页

作者： Rong-Rui Yang Yuan Yuan Chen Hao Ji Ma Guang-Hao Liu Fundamental Science on nuclear Safety and Simulation Technology laboratory College of Nuclear Science and TechnologyHarbin Engineering UniversityHarbin 150001China Department of Reactor Technology Beijing Institute of Nuclear EngineeringChina Nuclear Power Engineering Co.LtdBeijing 100089China

To benefit from recent advances in modeling and computational algorithms,as well as the availability of new covariance data,sensitivity and uncertainty analyses are needed to quantify the impact of uncertain sources on the design parameters of small prismatic high-temperature gascooled reactors(HTGRs).In particular,the contribution of nuclear data to the k_(eff)uncertainty is an important part of the uncertainty analysis of small-sized HTGR physical *** this study,a small-sized HTGR designed by China nuclear Power Engineering Co.,*** selected for k_(eff)uncertainty analysis during full lifetime burnup *** of the cold zero power(CZP)condition and full lifetime burnup process were constructed using the Reactor Monte Carlo Code RMC for neutron transport calculation,depletion calculation,and sensitivity and uncertainty *** the sensitivity analysis,the Contribution-Linked eigenvalue sensitivity/Uncertainty estimation via Track length importance Characterization(CLUTCH)method was applied to obtain sensitive information,and the "sandwich" method was used to quantify the k_(eff)*** also compared the k_(eff)uncertainties to other typical *** results show that ^(235)U is the largest contributor to k_(eff)uncertainty for both the CZP and depletion conditions,while the contribution of ^(239)Pu is not very significant because of the design of low discharge *** is worth noting that the radioactive capture reaction of ^(28)Si significantly contributes to the k_(eff)uncertainty owing to its specific fuel ***,the k_(eff)uncertainty during the full lifetime depletion process was relatively stable,only increasing by 1.12%owing to the low discharge burnup design of small-sized *** numerical results are beneficial for neutronics design and core parameters optimization in further uncertainty propagation and quantification study for small-sized HTGR.

关键词： Small-sized HTGR SU analysis nuclear data Burnup

Auger Electron Spectroscopy and Rut herford Backscattering-Channeling Study of Silicon Nitride Formation by Low Energy N^(+)_(2)Ion Implantation

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Chinese Physics Letters 1999年第2期16卷 120-122页

作者： CHAI Jian-wei YANG Guo-hua PAN Hao-chang CAO Jian-qing ZHU De-zhang XU Hong-jie laboratory of nuclear analysis Techniques Shanghai Institute of Nuclear ResearchChinese Academy of SciencesShanghai 201800

Direct nitridation of Si(100)surface by low energy N^(+)_(2)ion beam implantation at room temperature for differention doses and angles of incidence has been investigated by in-situ Auger electron spectroscopy and glancing Rutherford backscattering-channeling(RBS-C)*** results show that with increase of N^(+)_(2)ion dose the N concentration in the Si surface increases and reaches to a surface stoichiometry close to that of *** saturation dose and the thickness of the silicon nitride layer are related to the N^(+)_(2)ion *** nitride layer can be formed at incident angles of 0°-30°.At larger angles the degree of nitridation decreases and no nitride layer could be found at incident angles larger than 54°.The RBS-C results also suggest that a heavy damaged layer beneath the surface nitride layer can be formed due to ion beam implantation.

关键词： beneath Electron implantation

Approaches to eliminate near field artifact of MURA

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Chinese Physics C 2008年第1期32卷 80-82页

作者：王人松戎军艳魏龙 Key laboratory of nuclear analysis Techniques Institute of High Energy Physics CAS

Since the coded aperture technique has been successfully applied on X-ray imaging space telescopes, attentions of its development have also been cast on the application in medical imaging, for it has a very tempting quality to greatly enhance the detection sensitivity without gravely lowering the spacial resolution. But when the coded aperture technique is applied to image a nearby object, the so called ＂near-field artifact＂ comes up, that is, the reconstructed image has a sort of distortion. Among types of coded apertures the MURA （Modified Uniformly Redundant Array） is one of the most discussed. Roberto Arrcosi came up with the solution to remove the artifacts utilizing mask and antimask. In this article we present two ways to eliminate the second order aberration based on his work.

关键词： MURA coded aperture MLEM optical supplementary principle

An improved semi-implicit direct kinetics method for transient analysis of nuclear reactors

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nuclear Science and Techniques 2019年第11期30卷 108-126页

作者： Roozbeh Vadi Kamran Sepanloo School of nuclear Reactors and Safety Nuclear Science and Technology Research Institute

Semi-implicit direct kinetics(SIDK)is an innovative method for the temporal discretization of neutronic equations proposed by *** key approximation of the SIDK method is to substitute a timeaveraged quantity for the fission source term in the delayed neutron differential ***,these equations are decoupled from prompt neutron equations and an explicit analytical representation of precursor groups is obtained,which leads to a significant reduction in computational *** the fission source is not known in a time step,the original study suggested using a constant quantity pertaining to the previous time step for this purpose,and a reduction in the size of the time step was proposed to lessen the imposed ***,this remedy notably diminishes the main advantage of the SIDK *** discerned that if the original method is properly introduced into the algorithm of the point-implicit solver along with some modifications,the mentioned drawbacks will be mitigated *** test this idea,a novel multigroup,multi-dimensional diffusion code using the finitevolume method and a point-implicit solver is developed which works in both transient and steady *** addition to the SIDK,two other kinetic methods,i.e.,direct kinetics and higher-order backward discretization,are programmed into the diffusion code for comparison with the proposed *** final code is tested at different conditions of two well-known transient benchmark *** indicate that while the accuracy of the improved SIDK is closely comparable with the best available kinetic methods,it reduces the total time required for computation by up to 24%.

关键词： nuclear kinetics Semi-implicit direct kinetics Higher-order backward discretization Finite volume Point-implicit solver

Bayesian analysis of nuclear equation of state at high baryon density

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nuclear Science and Techniques 2023年第12期34卷 156-158页

作者： Long‑Gang Pang Xin‑Nian Wang Key laboratory of Quark and Lepton Physics(MOE) Institute of Particle PhysicsCentral China Normal UniversityWuhan 430079China nuclear Science Division Lawrence Berkeley National LaboratoryBerkeleyCA 94720USA

Bayesian analysis was employed to constrain the equation of state(EoS)of nuclear matter with a baryon density of up to six times the nuclear saturation density,using data from heavy-ion collisions at beam energies√S_... 详细信息

关键词： observations equation state

Loss of offsite power (LOOP) accident analysis by integration of deterministic and probabilistic approaches in Bushehr-1 VVER-1000/V446 nuclear power plant

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nuclear Science and Techniques 2022年第5期33卷 39-52页

作者： Mohsen Esfandiari Gholamreza Jahanfarnia Kamran Sepanloo Ehsan Zarifi Department of nuclear Engineering Science and Research BranchIslamic Azad UniversityTehranIran Reactor and nuclear Safety School Nuclear Science and Technology Research Institute(NSTRI)TehranIran

The results of an accident analysis for the loss of offsite power(LOOP)scenario in a reference Bushehr-1 VVER-1000/V446 nuclear power plant(NPP)are presented in this *** study attempted to provide a better analysis of LOOP accident management by integrating deterministic and probabilistic *** RELAP5 code was used to investigate the occurrence of specific thermal–hydraulic *** probabilistic safety assessment of the LOOP accident is presented using the SAPHIRE *** accident data were extracted from the Bushehr NPP final safety analysis reports and probabilistic safety analysis reports.A deterministic approach was used to reduce the core damage frequency in the probabilistic analysis of LOOP *** probabilistic approach was used to better observe the philosophy of defense in depth and safety margins in the deterministic analysis of the LOOP *** results show that the integration of the two approaches in LOOP accident investigations improved accident control.

关键词： Loss of offsite power Deterministic Probabilistic Integration RELAP5 SAPHIRE

Irradiation effect of yttria-stabilized zirconia by high dose dual ion beam irradiation

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Chinese Physics B 2014年第6期23卷 417-421页

作者：张艳文王绪刘士毅唐美雄赵子强张鹏王宝义曹兴忠 State Key laboratory of nuclear Physics and Technology Institute of Heavy Ion Physics Peking University Key laboratory of nuclear analysis Techniques Institute of High Energy Physics Chinese Academy of Sciences

Yttria-stabilized zirconia （YSZ） is irradiated with 2.0-MeV Au2＋ ions and 30-keV He＋ ions. Three types of He, Au, Au ＋ He （successively） ion irradiation are performed. The maximum damage level of a sequential dual ion beam implanted sample is smaller than single Au ion implanted sample. A comparable volume swelling is found in a sequential dual ion beam irradiated sample and it is also found in a single Au ion implanted sample. Both effects can be explained by the partial reorganization of the dislocation network into weakly damaged regions in the dual ion beam implanted YSZ. A vacancy-assisted helium trapping/diffusion mechanism in the dual ion beam irradiated condition is discussed. No phase transformation or amorphization behavior happens in all types of ion irradiated YSZ.

关键词： irradiation damage swelling helium diffusion

Performance of the plugged-in ^(22)Na based slow positron beam facility

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Chinese Physics C 2008年第3期32卷 243-246页

作者：王平马雁云秦秀波张哲曹兴忠于润升王宝义 Key laboratory of nuclear analysis Techniques Institute of High Energy PhysicsCASBeijing 100049China Graduate University of Chinese Academy of SciencesBeijing 100049China Key laboratory of nuclear analysis Techniques Institute of High Energy PhysicsCASBeijing 100049China

The Beijing intense slow positron beam facility is based on the 1.3 GeV linac of Beijing ElectronPositron Collider （BEPC） aiming to produce mono-energetic intense slow positron beam for material science investigation. The plugged-in 22Na based slow positron beam section has been newly constructed to supply continuous beam time for the debugging of positron annihilation measurement stations and improve the Beijing intense slow positron beam time using efficiency. Performance testing result of the plugged-in 22Na based slow positron beam facility are reviewed in this paper, with the measurement of the beam transport efficiency, the view of beam spot, the adjustment of beam position, the measurement of beam intensity and energy spread etc. included.

关键词： slow positron beam transport efficiency beam intensity energy spread

Effect of Cu on the boron segregation at grain boundaries and vacancy-type defects in ultra-low carbon micro-alloy steels

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Science China(Technological Sciences) 2014年第6期57卷 1135-1141页

作者： YANG RuiJie WU Ping LI XiangLong ZHANG ShiPing CHEN Sen WANG BaoYi JU Xin Department of Physics School of Mathematics and PhysicsUniversity of Science and Technology Beijing Key laboratory of nuclear analysis Techniques

By thermal neutron irradiation particle tracking autoradiography(PTA)technique,the development of boron segregation at grain boundaries in ultra-low carbon micro-alloy steels was investigated during cooling from 1150°C to 850°C,and the effect of Cu on boron segregation at grain boundaries was *** positron annihilation lifetime(PAL)technique,the changes of vacancy-type defects with temperatures and the effect of Cu on vacancy-type defects in the cooling process were *** show that,the concentration of boron at grain boundaries increases rapidly at the beginning of the cooling;after that,it begins to decrease;and then,it increases gradually *** addition of Cu not only increases the concentration of boron at grain boundaries but also speeds up the development process of boron segregation at grain *** the continuous cooling process,the addition of Cu significantly affects the change of vacancy-type defects with temperatures in ultra-low carbon micro-alloy steels.

关键词： particle tracking autoradiography(PTA) technique boron segregation at grain boundaries positron annihilation lifetime(PAL) technique vacancy-type defects ultra-low carbon micro-alloy steels